Use OTP 26.1 as OTP 26 in CI (backport #9486)

[mergify]

This is an automatic backport of pull request #9486 done by Mergify.
Cherry-pick of 75eb062 has failed:

On branch mergify/bp/v3.12.x/pr-9486
Your branch is up to date with 'origin/v3.12.x'.

You are currently cherry-picking commit 75eb0621fc.
  (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:   .bazelrc
	modified:   .github/workflows/check-build-system-equivalence.yaml
	modified:   .github/workflows/oci.yaml
	modified:   .github/workflows/test-authnz.yaml
	modified:   .github/workflows/test-selenium.yaml
	modified:   .github/workflows/update-otp-patches.yaml
	modified:   MODULE.bazel
	modified:   WORKSPACE
	modified:   bazel/platforms/BUILD.bazel
	modified:   packaging/docker-image/BUILD.bazel

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   .github/workflows/check-build-system-equivalence-release-branches.yaml
	both modified:   .github/workflows/test-windows.yaml

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

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