It seems it'd better to give best efforts for describing the guides for creating JIRAs and PRs as there are several discussions about this.
- We could add some pointers of CONTRIBUTING.md or wiki in README.md
- Adds an explicit warning in PULL_REQUEST_TEMPLATE, in particular, for some PRs trying to merge a branch to another branch, for example as below:
Please double check if your pull request is from a branch to a branch. It is probably wrong if the pull request title is "Branch 2.0" or "Merge ..." or if your pull request includes many commit logs unrelated to your changes to propose.
Please refer the mailing list.