walproposer: fix link error on debian 12 / ubuntu 22

[myrrc]

Problem

Linking walproposer library (e.g. cargo t) produces linker errors:
/home/myrrc/neon/pgxn/neon/walproposer_compat.c:169: undefined reference to `pg_snprintf'

The library with these symbols (libpgcommon.a) is present

Summary of changes

Changed order of libraries resolution for linker

[github-actions]

7073 tests run: 6758 passed, 0 failed, 315 skipped (full report)

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Flaky tests (3)

Postgres 17

• test_check_visibility_map: debug-x86-64

Postgres 16

• test_scrubber_physical_gc_ancestors[2]: release-arm64

Postgres 15

• test_pull_timeline[True]: release-x86-64

Code coverage* (full report)

• functions: 31.4% (8341 of 26534 functions)
• lines: 47.7% (65723 of 137703 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
17f0b49 at 2024-12-11T16:24:48.231Z :recycle:}