util/cgroup: fix InContainer for cgroup v2 (#48344)

[ti-chi-bot]

This is an automated cherry-pick of #48344

What problem does this PR solve?

Issue Number: close #48342

Problem Summary:

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
  below value is calculated using result of MemTotal
  before
  [2023/11/07 13:23:21.976 +08:00] [INFO] [merge.go:39] ["start to merge overlapping files"] [file-count=1000] [file-groups=17] [concurrency=16] [memory-limit=14.79GiB]
  after
  [2023/11/07 14:06:00.211 +08:00] [INFO] [merge.go:39] ["start to merge overlapping files"] [file-count=1000] [file-groups=17] [concurrency=16] [memory-limit=963.8MiB]
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[D3Hunter]

/lgtm

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: D3Hunter, hawkingrei

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-11-07 06:50:39.720537564 +0000 UTC m=+3540637.307647701: ☑️ agreed by hawkingrei.
• 2023-11-07 07:01:18.272241997 +0000 UTC m=+3541275.859352135: ☑️ agreed by D3Hunter.

[hawkingrei]

/retest