Fix windows crush

[Enrypint]

stable-diffusion-webui\extensions\tag-autocomplete\scripts\tag_autocomplete_helper.py", line 18, in get_tags_base_path
    if (script_path.is_relative_to(EXT_PATH)):
AttributeError: 'WindowsPath' object has no attribute 'is_relative_to'

This fix solves that problem. If the code is not very nice, you can suggest something better.

[DominikDoom]

I'm on windows too and this error doesn't happen to me. Which Python version are you using?
is_relative_to was introduced with Python 3.9, so for 3.10.6 which the webui recommends you should have no problem.

Now I'm not against your version, just wondering if it's necessary since I do find the "modern" version a bit more elegant.

[Enrypint]

I tried to find information about this, but I didn't realize it was only in the new python. I used python 3.8 and python and some online compiler site, and both gave a similar error. So I thought it only worked on linux. Sorry for the false PR.