Cherry-pick #25701 to 7.13: Do not apply config if newer is available during restart

[michalpristas]

Cherry-pick of PR #25701 to 7.13 branch. Original message:

What does this PR do?

Theory is that there is a very rare condition when restart and pushConfig has a race and config used in restart overwrites the one used with push.

Why is it important?

Fixes: #25637

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

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Build stats

• Build Cause: Pull request #25704 opened

• Start Time: 2021-05-13T12:58:12.687+0000

• Duration: 56 min 22 sec

• Commit: aed4511

Test stats 🧪

Test	Results
Failed	0
Passed	6796
Skipped	24
Total	6820

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Test stats 🧪

Test	Results
Failed	0
Passed	6796
Skipped	24
Total	6820