update offsets.pyx to fix #60647
- [x ] closes #60647 (Replace xxxx with the GitHub issue number)
- [ ] [Tests added and passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#writing-tests) if fixing a bug or adding a new feature
- [ ] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).
- [ ] Added [type annotations](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#type-hints) to new arguments/methods/functions.
- [ ] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.

Sorry for not adding a test case for this. I'll set it up once I get home and can work on my PC—my current laptop is too slow to handle the full testing environment.
 Also, I noticed the unit tests failed. Again, I will fix them once I get home. Thanks for working on this fix for #60647!

This change successfully removes the code path containing the specific line (`holidays = holidays + calendar.holidays().tolist()`) identified in the issue and the comments.

However, there are a few points that probably deserve some attention:

**Removed Functionality:** This fix works by removing the `if-else` block. Was the functionality within that block (handling a non-numpy `calendar` object passed with `holidays`) intended or ever valid? Removing it is a potentially breaking change that should ideally be documented.

**Exception Type:** Raising `ApplyTypeError` here is a bit unusual, as it's typically for arithmetic operations returning `NotImplemented`. Would a `ValueError` or `TypeError` be more appropriate to signal invalid arguments during the setup phase?
 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.