Update PR template.

Removed documentation task, as most of it is hosted externally for now.

Author: p-pautov

.github/pull_request_template.md

@@ -1,6 +1,6 @@
 ### Proposed changes
 
-Describe the use case and detail of the change. If this PR addresses an issue on GitHub, make sure to include a link to that issue using one of the [supported keywords](https://docs.github.com/en/github/managing-your-work-on-github/linking-a-pull-request-to-an-issue) here in this description (not in the title of the PR).
+Describe the use case and detail of the change. If this PR addresses an issue on GitHub, make sure to include a link to that issue using `fix` [keyword](https://docs.github.com/en/github/managing-your-work-on-github/linking-a-pull-request-to-an-issue) here in this description and in corresponding commit message.
 
 ### Checklist
 
@@ -9,4 +9,3 @@ Before creating a PR, run through this checklist and mark each as complete.
 - [ ] I have read the [`CONTRIBUTING`](https://github.com/nginxinc/nginx-otel/blob/main/CONTRIBUTING.md) document
 - [ ] If applicable, I have added tests that prove my fix is effective or that my feature works
 - [ ] If applicable, I have checked that any relevant tests pass after adding my changes
-- [ ] I have updated any relevant documentation ([`README.md`](https://github.com/nginxinc/nginx-otel/blob/main/README.md) and [`CHANGELOG.md`](https://github.com/nginxinc/nginx-otel/blob/main/CHANGELOG.md))