[2pt] Create GitHub Actions workflows to translate documentation

[artembo]

The documentation translation process should be automated. We need to implement a set of tasks at each stage of tech writer's workflow to maintain 100% translation for each repository containing documentation.

• Tech writer creates PR with a documentation update (rst sources).
  • (push-translation on pull_request) GitHub workflow builds po files from rst and sends them to the same name branch in Crowdin
• Pull translations back
  • (pull-translation on workflow_dispatch) When translation of the corresponding changes is ready, tech writer manually triggers GitHub workflow for the translated branch (PR branch)
• Tech writer or someone responsible merges PR
  • (upload-translation on push to master) GithHub workflow upload merged translations from po files into Crowdin master (or main) branch