Increase max connection for replica to prevent test flukyness

[knizhnik]

Problem

See #10167
Too small number of max_connections (2) can cause failures of test_physical_replication_config_mismatch_too_many_known_xids test

Summary of changes

Increase max_connections to 5

[github-actions]

7227 tests run: 6875 passed, 0 failed, 352 skipped (full report)

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Flaky tests (1)

Postgres 14

• test_pg_regress[4]: release-arm64

Code coverage* (full report)

• functions: 31.2% (8414 of 26961 functions)
• lines: 48.0% (66802 of 139237 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
db77e9d at 2025-01-08T08:17:01.375Z :recycle:}