Test coverage for branch-only submodule

[dahlbyk]

Proves that #604 is fixed.

Also:

• Added diff to Resources/.gitattributes for commonly-modified text files - respected locally even if GitHub seems to ignore .gitattributes.
• Made remote.origin.url relative in all submodule_wd/.git/modules.
• Added ignore rule for files we don't really need in the Resources repos (e.g. ref logs and info/exclude) - fewer files to copy = faster tests.

[dahlbyk]

Remove extra test resource files

Oops, need reflog for standard repo tests.

[nulltoken]

@dahlbyk 🆒 ‼️ Any chance you could simplify the history a bit?

[dahlbyk]

Sure, what do you have in mind?

[nulltoken]

Maybe squash the last two commits together as the first one doesn't build by itself?

[nulltoken]

@dahlbyk ping?

[dahlbyk]

Better?

[nulltoken]

@jamill @whoisj You're more into submodules than me. Could you please take a look at this PR?

[whoisj]

@nulltoken @dahlbyk I will look at this, but today I'm heads down on something else. Can we wait until tomorrow?

[nulltoken]

@dahlbyk ❤️

@whoisj Thanks!

Can we wait until tomorrow?

I think so. Some of those commits are one year old.

[whoisj]

LGTM

@dahlbyk 🙇 thanks!

[nulltoken]

🚢'd