Revert "safekeeper: check for non-consecutive writes in safekeeper.rs"

[jcsp]

Reverts #8640

This broke test_last_log_term_switch via a merge race of some kind.

[github-actions]

2198 tests run: 2134 passed, 0 failed, 64 skipped (full report)

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Flaky tests (4)

Postgres 16

• test_combocid: debug
• test_forward_compatibility: debug
• test_lfc_resize: debug
• test_lagging_sk: debug

Code coverage* (full report)

• functions: 32.4% (7235 of 22310 functions)
• lines: 50.4% (58435 of 115922 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
19c9231 at 2024-08-20T11:42:48.119Z :recycle:}