Update WordPress

[mikelittle]

Updates WordPress to 6.8.7

[github-actions]

Successfully created backport PR for v24-branch:

• [Backport v24-branch] Update WordPress #988

[github-actions]

Successfully created backport PR for v23-branch:

• [Backport v23-branch] Update WordPress #989

[github-actions]

Backport failed for v24-branch, because it was unable to cherry-pick the commit(s).

Please cherry-pick the changes locally and resolve any conflicts.

git fetch origin v24-branch
git worktree add -d .worktree/backport-986-to-v24-branch origin/v24-branch
cd .worktree/backport-986-to-v24-branch
git switch --create backport-986-to-v24-branch
git cherry-pick -x a13cab3b2605521251c239f8d5cddd979820b60c

[github-actions]

After resolving conflicts, continue with:

# Add the resolved files
git add .
# Continue the cherry-pick
git cherry-pick --continue
# Push the branch to GitHub
git push --set-upstream origin backport-986-to-v24-branch
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktree/backport-986-to-v24-branch

Then create a pull request using the GitHub CLI:

gh pr create --base v24-branch --head backport-986-to-v24-branch --title "[Backport v24-branch] Update WordPress" --body "Backport of #986 to \`v24-branch\`."