Adding 8.6.2 changelog to 8.7 branch

[pierrehilbert]

What does this PR do?

Close #35580

Why is it important?

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.

Author's Checklist

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• Start Time: 2023-07-24T13:00:25.543+0000

• Duration: 8 min 52 sec

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