resource_control: update resource control about background example

[nolouch]

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• This PR is translated from: *: update resource control about background example docs-cn#15469
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• Delete files
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[hfxsd]

/verify

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-12-06 07:52:20.148280648 +0000 UTC m=+1600368.813506844: ☑️ agreed by hfxsd.
• 2023-12-06 08:06:14.300026145 +0000 UTC m=+1601202.965252334: ☑️ agreed by Oreoxmt.

[Oreoxmt]

/approve

[ti-chi-bot]

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.4: #15609.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.5: #15610.