CI(vm-compute-node-image): specify debain version

[bayandin]

Problem

Summary of changes

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]

5065 tests run: 4906 passed, 1 failed, 158 skipped (full report)

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Failures on Postgres 17

• test_sharding_split_failures[failure17]: release-x86-64

# Run all failed tests locally:
scripts/pytest -vv -n $(nproc) -k "test_sharding_split_failures[release-pg17-failure17]"

Flaky tests (6)

Postgres 17

• test_pageserver_compaction_smoke: release-x86-64
• test_ondemand_wal_download_in_replication_slot_funcs: release-x86-64
• test_subscriber_restart: release-x86-64
• test_restart_endpoint_after_switch_wal: release-x86-64

Postgres 14

• test_replica_start_scan_clog_crashed_xids: release-x86-64
• test_subscriber_restart: release-x86-64

Code coverage* (full report)

• functions: 32.0% (7494 of 23395 functions)
• lines: 50.0% (60475 of 120876 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
b9c262b at 2024-09-26T23:50:22.490Z :recycle:}