ci: spelling: remove branch / tag filtering

[jsoref]

This repository tends to use /s in branch names.
Unfortunately, branch: "*" at present only matches a single
level, which means it would match a branch named foo but not bar/foo.

Given that I don't think this repository is actively using tags,
and given that the general cost for the spell checker isn't particularly
high, it's better to remove the filtering so that all branches get
checked.

Worst case, a branch that is also tagged and has spelling errors
will get two comments complaining about those spelling errors.

Summary of the Pull Request

References

PR Checklist

• Closes #xxx
• CLA signed. If not, go over here and sign the CLA
• Tests added/passed
• Requires documentation to be updated
• I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx

Detailed Description of the Pull Request / Additional comments

Validation Steps Performed

Testing by @DHowett-MSFT

• 4357854 -- null commit on DTI no slash branch
• 3055618 -- null commit on DTI with slash branch
• 065a96d -- null commit on master
• 3377781 -- null commit on master with slashes

[DHowett-MSFT]

Thanks!

[jsoref]

Ok, I looked more carefully and https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions#filter-pattern-cheat-sheet indicates that I could have just changed * to ** and things would have worked. sigh

That's ok. For now, I vote for leaving it as is. I'll update my samples somewhere to suggest ** going forward.

I still need to look into why the scheduler isn't doing anything particularly exciting. But.... maybe next week. So far, it looks like the basic checker is doing enough good.