update deps and add mergify config for v0.26.x release branch (backport #1853)

[mergify]

---

This is an automatic backport of pull request #1853 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 7866ee2 has failed:

On branch mergify/bp/release/v0.26.x/pr-1853
Your branch is up to date with 'origin/release/v0.26.x'.

You are currently cherry-picking commit 7866ee2f.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   .github/mergify.yml
	modified:   go.mod

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   go.sum

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally