test: fix ambiguous OID prefix canonical name test cases

[cpb]

When submitting this PR:

• Map 'Caleb' to 'Caleb Buxton' #310

I found that there were 2 tests failing in main.

I observed that other simple mapping PRs had unrelated failures:

• Add Takuma Yoshida mapping #286
• Map npezza93 to Nick Pezza #288

I'm proposing:

1. Clarifying the ambiguous OID case from the Rails checkout is stale failure case
2. Disambiguate two assert_contributor_names cases by using the full SHA

[cpb]

@fxn Thanks for chatting with me near the swag/coat check counter at Rails World between talks. I agree with maintaining the aesthetics of the test and PR, so have shorted the SHAs to achieve the disambiguation for these two cases.

I'll follow up with tooling to support reducing the effort to resolve other such failures, as we discussed.

Thank you for your time, I hope you had a great time at Rails World!

[cpb]

@fxn Thanks for chatting with me near the swag/coat check counter at Rails World between talks. I agree with maintaining the aesthetics of the test and PR, so have shorted the SHAs to achieve the disambiguation for these two cases.

I'll follow up with tooling to support reducing the effort to resolve other such failures, as we discussed.

Thank you for your time, I hope you had a great time at Rails World!

The changes in this PR are made redundant by the tooling and changes introduced in this PR:

• test: standardize to 8 character commit SHA1 in assert_contributor_names #314

[fxn]

Hi man! Thanks a lot for this. I have several things in my plate, but I'll eventually work on your proposal!