CI tidy up (#6756)

Author: achamayou

.azure-pipelines-release.yml

@@ -1,13 +1,5 @@
 Documents the various GitHub Actions workflows, the role they fulfil and 3rd party dependencies if any.
 
-# Backport
-
-Attempts to auto-open backport PRs from main to LTS branch(es) whenever possible. This works well in the absence of conflicts, typically early on during the life of an LTS, and less well later. The alternatives are running the backport tool manually, or cherry picking commits.
-Triggered when the label `auto-backport` is applied to a PR, along with the `X.*-todo` label to set the target branch.
-
-File: `backport.yml`
-3rd party dependencies: `sorenlouv/backport-github-action@main`
-
 # Bencher
 
 Builds and runs CCF performance tests, both end to end and micro-benchmarks. Results are posted to bencher.dev, and [plotted to make regressions obvious](https://bencher.dev/console/projects/ccf/plots).