Remove the tests for pg_anon

[a-masterov]

Problem

We are removing the pg_anon v1 extension from Neon. So we don't need to test it anymore and can remove the code for simplicity.

Summary of changes

The code required for testing pg_anon is removed.

[github-actions]

7359 tests run: 6979 passed, 0 failed, 380 skipped (full report)

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Flaky tests (8)

Postgres 17

• test_metrics_normal_work: release-x86-64, debug-x86-64
• test_timeline_archive[4]: debug-x86-64

Postgres 16

• test_isolation[None]: release-x86-64
• test_metrics_normal_work: release-x86-64, release-arm64

Postgres 15

• test_scrubber_physical_gc_ancestors[None]: release-arm64
• test_metrics_normal_work: release-x86-64

Code coverage* (full report)

• functions: 33.6% (8448 of 25111 functions)
• lines: 49.2% (70805 of 143967 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
7daf17a at 2025-01-21T16:39:25.189Z :recycle:}

[bayandin]

Should we remove the extension itself?

[a-masterov]

Should we remove the extension itself?

Let's try.

[tristan957]

Are we sure that there are no users using pg_anon at the moment?

[bayandin]

Are we sure that there are no users using pg_anon at the moment?

See https://github.com/neondatabase/cloud/issues/22663

[tristan957]

Sounds like we just have one user left. Is someone reaching out to that user?

[tristan957]

Why are we making changes in the compute dockerfile?

[a-masterov]

Why are we making changes in the compute dockerfile?

We have to have the sources of the extension to run the tests.
As we build the extension in the compute Dockerfile, we build the new image to run the tests neon-test-extensions as a layer of the compute Dockerfile. So when we want to remove some tests of extensions, we have to remove them from the compute Dokerfile.
Here is the section of the workflow where the image is built.