Wrote test for Issue#29576 with resampling in non-unitary quarters

[joshdelg]

• closes startingMonth ignored on non-unitary Quarter periods #29576
• Added test to tests/resample/test_datetime_index.py following expected and actual output of original commenter
• All [code checks passed] (https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).

[mroeschke]

Looks like the tests are failing, and Mambaforge-Darwin-x86_64.sh was accidentally committed

[joshdelg]

Noticed the tests failed, I don't think the issue was fixed. Is the the expected output given in the issue description what the test should anticipate?

[mroeschke]

I don't think expected is correctly constructed to match #29576 (comment)

[mroeschke]

Thanks for the pull request, but it appears to have gone stale. If interested in continuing, please merge in the main branch, address any review comments and/or failing tests, and we can reopen.