test: copy dict to avoid error on retry (#8811)

there is no "const" in python, so when we modify the global dict, it
will remain that way on the retry. fix to not have it influence other
tests which might be run on the same runner.

evidence:
<https://neon-github-public-dev.s3.amazonaws.com/reports/pr-8625/10513146742/index.html#/testresult/453c4ce05ada7496>

test_runner/fixtures/pageserver/utils.py

@@ -430,12 +430,17 @@ def enable_remote_storage_versioning(
     return response
 
 
-MANY_SMALL_LAYERS_TENANT_CONFIG = {
-    "gc_period": "0s",
-    "compaction_period": "0s",
-    "checkpoint_distance": 1024**2,
-    "image_creation_threshold": 100,
-}
+def many_small_layers_tenant_config() -> Dict[str, Any]:
+    """
+    Create a new dict to avoid issues with deleting from the global value.
+    In python, the global is mutable.
+    """
+    return {
+        "gc_period": "0s",
+        "compaction_period": "0s",
+        "checkpoint_distance": 1024**2,
+        "image_creation_threshold": 100,
+    }
 
 
 def poll_for_remote_storage_iterations(remote_storage_kind: RemoteStorageKind) -> int:

test_runner/regress/test_s3_restore.py

@@ -8,9 +8,9 @@ from fixtures.neon_fixtures import (
     PgBin,
 )
 from fixtures.pageserver.utils import (
-    MANY_SMALL_LAYERS_TENANT_CONFIG,
     assert_prefix_empty,
     enable_remote_storage_versioning,
+    many_small_layers_tenant_config,
     wait_for_upload,
 )
 from fixtures.remote_storage import RemoteStorageKind, s3_storage
@@ -33,7 +33,7 @@ def test_tenant_s3_restore(
 
     # change it back after initdb, recovery doesn't work if the two
     # index_part.json uploads happen at same second or too close to each other.
-    initial_tenant_conf = MANY_SMALL_LAYERS_TENANT_CONFIG
+    initial_tenant_conf = many_small_layers_tenant_config()
     del initial_tenant_conf["checkpoint_distance"]
 
     env = neon_env_builder.init_start(initial_tenant_conf)
@@ -50,7 +50,7 @@ def test_tenant_s3_restore(
     tenant_id = env.initial_tenant
 
     # now lets create the small layers
-    ps_http.set_tenant_config(tenant_id, MANY_SMALL_LAYERS_TENANT_CONFIG)
+    ps_http.set_tenant_config(tenant_id, many_small_layers_tenant_config())
 
     # Default tenant and the one we created
     assert ps_http.get_metric_value("pageserver_tenant_manager_slots", {"mode": "attached"}) == 1

test_runner/regress/test_storage_controller.py

@@ -23,11 +23,11 @@ from fixtures.neon_fixtures import (
 )
 from fixtures.pageserver.http import PageserverHttpClient
 from fixtures.pageserver.utils import (
-    MANY_SMALL_LAYERS_TENANT_CONFIG,
     assert_prefix_empty,
     assert_prefix_not_empty,
     enable_remote_storage_versioning,
     list_prefix,
+    many_small_layers_tenant_config,
     remote_storage_delete_key,
     timeline_delete_wait_completed,
 )
@@ -654,7 +654,7 @@ def test_storage_controller_s3_time_travel_recovery(
         tenant_id,
         shard_count=2,
         shard_stripe_size=8192,
-        tenant_config=MANY_SMALL_LAYERS_TENANT_CONFIG,
+        tenant_config=many_small_layers_tenant_config(),
     )
 
     # Check that the consistency check passes

test_runner/regress/test_tenant_delete.py

@@ -9,9 +9,9 @@ from fixtures.neon_fixtures import (
 )
 from fixtures.pageserver.http import PageserverApiException
 from fixtures.pageserver.utils import (
-    MANY_SMALL_LAYERS_TENANT_CONFIG,
     assert_prefix_empty,
     assert_prefix_not_empty,
+    many_small_layers_tenant_config,
     wait_for_upload,
 )
 from fixtures.remote_storage import RemoteStorageKind, s3_storage
@@ -76,7 +76,7 @@ def test_tenant_delete_smoke(
 
     env.neon_cli.create_tenant(
         tenant_id=tenant_id,
-        conf=MANY_SMALL_LAYERS_TENANT_CONFIG,
+        conf=many_small_layers_tenant_config(),
     )
 
     # Default tenant and the one we created
@@ -215,7 +215,7 @@ def test_tenant_delete_races_timeline_creation(neon_env_builder: NeonEnvBuilder)
     # (and there is no way to reconstruct the used remote storage kind)
     remote_storage_kind = RemoteStorageKind.MOCK_S3
     neon_env_builder.enable_pageserver_remote_storage(remote_storage_kind)
-    env = neon_env_builder.init_start(initial_tenant_conf=MANY_SMALL_LAYERS_TENANT_CONFIG)
+    env = neon_env_builder.init_start(initial_tenant_conf=many_small_layers_tenant_config())
     ps_http = env.pageserver.http_client()
     tenant_id = env.initial_tenant
 
@@ -330,7 +330,7 @@ def test_tenant_delete_scrubber(pg_bin: PgBin, neon_env_builder: NeonEnvBuilder)
 
     remote_storage_kind = RemoteStorageKind.MOCK_S3
     neon_env_builder.enable_pageserver_remote_storage(remote_storage_kind)
-    env = neon_env_builder.init_start(initial_tenant_conf=MANY_SMALL_LAYERS_TENANT_CONFIG)
+    env = neon_env_builder.init_start(initial_tenant_conf=many_small_layers_tenant_config())
 
     ps_http = env.pageserver.http_client()
     # create a tenant separate from the main tenant so that we have one remaining

test_runner/regress/test_timeline_delete.py

@@ -16,9 +16,9 @@ from fixtures.neon_fixtures import (
 )
 from fixtures.pageserver.http import PageserverApiException
 from fixtures.pageserver.utils import (
-    MANY_SMALL_LAYERS_TENANT_CONFIG,
     assert_prefix_empty,
     assert_prefix_not_empty,
+    many_small_layers_tenant_config,
     poll_for_remote_storage_iterations,
     timeline_delete_wait_completed,
     wait_for_last_record_lsn,
@@ -782,7 +782,7 @@ def test_timeline_delete_resumed_on_attach(
     remote_storage_kind = s3_storage()
     neon_env_builder.enable_pageserver_remote_storage(remote_storage_kind)
 
-    env = neon_env_builder.init_start(initial_tenant_conf=MANY_SMALL_LAYERS_TENANT_CONFIG)
+    env = neon_env_builder.init_start(initial_tenant_conf=many_small_layers_tenant_config())
 
     tenant_id = env.initial_tenant