tests: exclude compatibility tests by default (#3975)

This allows to skip compatibility tests based on `CHECK_ONDISK_DATA_COMPATIBILITY` environment variable. When the variable is missing (default) compatibility tests wont be run.

.github/workflows/build_and_test.yml

@@ -338,6 +338,7 @@ jobs:
           rerun_flaky: true
         env:
           TEST_RESULT_CONNSTR: ${{ secrets.REGRESS_TEST_RESULT_CONNSTR }}
+          CHECK_ONDISK_DATA_COMPATIBILITY: nonempty
 
       - name: Merge and upload coverage data
         if: matrix.build_type == 'debug'

test_runner/regress/test_compatibility.py

@@ -34,9 +34,15 @@ from pytest import FixtureRequest
 # - check_neon_works performs the test itself, feel free to add more checks there.
 #
 
+check_ondisk_data_compatibility_if_enabled = pytest.mark.skipif(
+    os.environ.get("CHECK_ONDISK_DATA_COMPATIBILITY") is None,
+    reason="CHECK_ONDISK_DATA_COMPATIBILITY env is not set",
+)
+
 
 # Note: if renaming this test, don't forget to update a reference to it in a workflow file:
 # "Upload compatibility snapshot" step in .github/actions/run-python-test-set/action.yml
+@check_ondisk_data_compatibility_if_enabled
 @pytest.mark.xdist_group("compatibility")
 @pytest.mark.order(before="test_forward_compatibility")
 def test_create_snapshot(neon_env_builder: NeonEnvBuilder, pg_bin: PgBin, test_output_dir: Path):
@@ -81,6 +87,7 @@ def test_create_snapshot(neon_env_builder: NeonEnvBuilder, pg_bin: PgBin, test_o
     # Directory `test_output_dir / "compatibility_snapshot_pg14"` is uploaded to S3 in a workflow, keep the name in sync with it
 
 
+@check_ondisk_data_compatibility_if_enabled
 @pytest.mark.xdist_group("compatibility")
 @pytest.mark.order(after="test_create_snapshot")
 def test_backward_compatibility(
@@ -134,6 +141,7 @@ def test_backward_compatibility(
     ), "Breaking changes are allowed by ALLOW_BACKWARD_COMPATIBILITY_BREAKAGE, but the test has passed without any breakage"
 
 
+@check_ondisk_data_compatibility_if_enabled
 @pytest.mark.xdist_group("compatibility")
 @pytest.mark.order(after="test_create_snapshot")
 def test_forward_compatibility(