Read cplane events from regional redis

[khanova]

Problem

Actually read redis events.

Summary of changes

This is revert of #7350 + fixes. So, it makes sense to review everything except the first commit: https://github.com/neondatabase/neon/pull/7352/files/4ac8eddacdd5894e162f29b728b208d69d4c1832..83ba900fc6a67ed7fe0385e1f22ddc7fef754436

• Fixed events parsing
• Added timeout after connection failure
• Separated regional and global redis clients.

Checklist before requesting a review

• I have performed a self-review of my code.
• If it is a core feature, I have added thorough tests.
• Do we need to implement analytics? if so did you add the relevant metrics to the dashboard?
• If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section.

Checklist before merging

• Do not forget to reformat commit message to not include the above checklist

[github-actions]

2748 tests run: 2630 passed, 0 failed, 118 skipped (full report)

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Flaky tests (1)

Postgres 14

• test_ts_of_lsn_api: debug

Code coverage* (full report)

• functions: 28.0% (6428 of 22958 functions)
• lines: 46.6% (45017 of 96547 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
9261280 at 2024-04-11T18:37:43.251Z :recycle:}