S3 restore test: Use a workaround to enable moto's self-copy support (#6594)

While working on https://github.com/getmoto/moto/pull/7303 I discovered
that if you enable bucket encryption, moto allows self-copies. So we can
un-ignore the test. I tried it out locally, it works great.

Followup of #6533, part of
https://github.com/neondatabase/cloud/issues/8233

test_runner/fixtures/pageserver/utils.py

@@ -356,10 +356,26 @@ def enable_remote_storage_versioning(
     """
     Enable S3 versioning for the remote storage
     """
-    # local_fs has no
+    # local_fs has no support for versioning
     assert isinstance(remote, S3Storage), "localfs is currently not supported"
     assert remote.client is not None
 
+    # The SDK supports enabling versioning on normal S3 as well but we don't want to change
+    # these settings from a test in a live bucket (also, our access isn't enough nor should it be)
+    assert not remote.real, "Enabling storage versioning only supported on Mock S3"
+
+    # Workaround to enable self-copy until upstream bug is fixed: https://github.com/getmoto/moto/issues/7300
+    remote.client.put_bucket_encryption(
+        Bucket=remote.bucket_name,
+        ServerSideEncryptionConfiguration={
+            "Rules": [
+                {
+                    "ApplyServerSideEncryptionByDefault": {"SSEAlgorithm": "AES256"},
+                    "BucketKeyEnabled": False,
+                },
+            ]
+        },
+    )
     # Note that this doesnt use pagination, so list is not guaranteed to be exhaustive.
     response = remote.client.put_bucket_versioning(
         Bucket=remote.bucket_name,

test_runner/regress/test_s3_restore.py

@@ -1,7 +1,6 @@
 import time
 from datetime import datetime, timezone
 
-import pytest
 from fixtures.neon_fixtures import (
     NeonEnvBuilder,
     PgBin,
@@ -32,7 +31,6 @@ def test_tenant_s3_restore(
         remote_storage = neon_env_builder.pageserver_remote_storage
         assert remote_storage, "remote storage not configured"
         enable_remote_storage_versioning(remote_storage)
-        pytest.skip("moto doesn't support self-copy: https://github.com/getmoto/moto/issues/7300")
 
     env = neon_env_builder.init_start(initial_tenant_conf=MANY_SMALL_LAYERS_TENANT_CONFIG)
     env.pageserver.allowed_errors.extend(