feat: add contribution guide

[tyler36]

A comment on #26 requested commit messages follow "Semantic Commit Messages" and suggested following https://gist.github.com/joshbuchea/6f47e86d2510bce28f8e7f42ae84c716 .

If this is requirement for MRs, we should consider:

• documenting this in the README
• adding a contribution file outlining this (and other) requirements
• adding a workflow that validates commit messages (DDEV does for MR messages, not sure about individual commits within)

[rfay]

And of course, my favorite is configuring the repo to use squashing, and use the title of the PR for the squashed commit. Then it's easier to read the whole commit history, and the rule only has to be applied one place.

[seebeen]

I'll write the contrib guide. Regarding the config.

Squashing is OK.
Using PR titles for commits - not so much. IMHO, PR titles should be descriptive and human readable.

PR Title: Done this and this for this and this
commit msg: fix: Sorted docker compose file

Fixes #36

Feel free to reconfigure the repo for squash commits @rfay - don't have much experience with that 😅

[seebeen]

• adding a workflow that validates commit messages (DDEV does for MR messages, not sure about individual commits within)

Generally speaking - Commit msg validation workflow is a bit overkill. Husky + commitizen can (and should) be used to enforce commits with hooks.

• documenting this in the README
• adding a contribution file outlining this (and other) requirements

Will make a contributing.md and set everything up.

[rfay]

I changed it to squash commits:

[rfay]

If you have a requirement for the resultant squashed commit, I recommend that you go in there and click on "default message" and change it to what you like:

IMO, requiring a specific (readable) format for the title is the easiest way to go. We use this technique and just enforce the PR title. But of course, you get to do it the way you like. https://ddev.readthedocs.io/en/stable/developers/building-contributing/#pull-request-title-guidelines

[seebeen]

You're becoming my favourite person on GH 😊😊😊