Changelog rewording for 7.0

[The-Compiler]

See the comments in https://github.com/pytest-dev/pytest/pull/8814/files#diff-e02b5aa2806cf9086c18c4d38b880df457d9313bf02ba108d58e67336abbab66 - those should be fixed in the individual changelog/*.rst files.

Ignore the first comment about the title, that's tracked in #8817.

[ericluoliu]

Working on this

[ericluoliu]

Made the pull request
I noticed a comment on 8411.trivial.rst to perhaps drop the contents of the file but I wasn't sure what needed to be done so I just left it as is for now.