style: Remove trailing whitespace and missing final newlines

[hyperupcall]

In #272, one section stated to "delete trailing spaces". This does that, and also missing final newlines (so files are files by POSIX)

This also integrates editorconfig-checker with GitHub Actions so the style will continue to remain consistent. It runs only on files that have changed for speed. I used editorconfig-checker because integrating shfmt might have changed more lines than what might be considered necessary; editorconfig-checker checks the bare minimum.

The only real code change resulting from this is in tools/uninstall.sh

[akinomyoga]

Thank you for your work!

I actually left these tasks in #272 to avoid possible conflicts with existing PRs, but I think now it is time to actively work on them. When I took over the maintenance of this project, there were about 50 or more pending PRs, which I hadn't time to look into. But we have already processed most of the important PRs that existed at that time.

---

Maybe we do not have to decide it in this PR, but another thing that I might need to rethink is the format of the commit message. There were really no explicit rules for the format of the commit message, but as for the first line, I was loosely following the suggestion made in CONTRIBUTING.md of #90.

<FILE>: <Summary>

<Description>
<Fixes/Bug>: #<BUG_NUMBER>
Signed-off-by: <name> <surname> <e-mail>

However, I actually have no plan to merge #90. Maybe I would pick some changes from #90, but I probably reject most of the changes suggested in #90.

Also, personally, I'd like to switch to Conventional Commits as in this PR. What do you think?

edit: I now noticed #86, which describes a proposal for the beginning line of the commit message in detail.

[akinomyoga]

@hyperupcall

[hyperupcall]

I actually left these tasks in #272 to avoid possible conflicts with existing PRs, but I think now it is time to actively work on them. When I took over the maintenance of this project, there were about 50 or more pending PRs, which I hadn't time to look into. But we have already processed most of the important PRs that existed at that time.

👍

Also, personally, I'd like to switch to Conventional Commits as in this PR. What do you think?

I think Conventional Commits is good to use - it's what is used at asdf too, but we might need to add a few extra things. I looked at #86, and I think it's heading in the right direction, but I would add a few more things. For example, it suggests something like git-avh: Doing something here or completions: Fixed #GITHUB-ISSUE-NUMBER for a git-avh related completion feature. But, I would do something like completions(git-avh): Doing something here #GITHUB-ISSUE-NUMBER

I do apologize for my late reply, I know I started work on this a week ago

[hyperupcall]

I looked things over and the new changes look good to me! I'll look over #432 tomorrow morning

[akinomyoga]

Thanks!