Enable the pg_regress tests on staging for PG17

[a-masterov]

Problem

Currently, we run the pg_regress tests only for PG16
However, PG17 is a part of Neon and should be tested as well

Summary of changes

Modified the workflow and added a patch for PG17 enabling the pg_regress tests.
The problem with leftovers was solved by using branches.

[github-actions]

7051 tests run: 6726 passed, 0 failed, 325 skipped (full report)

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Flaky tests (6)

Postgres 17

• test_timeline_archival_chaos: release-arm64

Postgres 15

• test_prefetch[4]: release-arm64
• test_scrubber_physical_gc_ancestors[2]: release-arm64

Postgres 14

• test_prefetch[None]: release-arm64
• test_prefetch[4]: release-x86-64
• test_pull_timeline[True]: release-x86-64

Code coverage* (full report)

• functions: 31.4% (8335 of 26528 functions)
• lines: 47.7% (65574 of 137367 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
427a573 at 2024-12-09T18:17:54.185Z :recycle:}

[bayandin]

Looks good!
Need to delete one more extra file, and we're good to merge it! Well done!