[BUG] Minimize merge conflicts in CHANGELOG #18475
Description
Describe the bug
One common pain point I have as a contributor to this repo is making sure that my PRs have no conflicts in the CHANGELOG file. As soon as another PR is merged that has an entry in the same section of the CHANGELOG as the change I am introducing, there will be conflicts.
It should be possible to introduce a merge policy that tells git to take the union of both sides of the conflict since each side is mutually exclusive.
A simple change like this could reduce a lot of pain on maintainers to re-run flaky CI multiple times to resolve a simple change in the CHANGELOG.
Related component
Build
To Reproduce
Check any dependabot PR after merging another dependabot PR
Expected behavior
Automatically union the changes