Added file paths to ignore in linter scripts/validate_unwanted_patterns.py

[ShaharNaveh]

• closes #xxxx
• tests added / passed
• passes black pandas
• passes git diff upstream/master -u -- "*.py" | flake8 --diff
• whatsnew entry

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While running ./ci/code_checks.sh lint on my local machine I got the output of:

Check for use of not concatenated strings
./asv_bench/env/40d026129f63c107b1ac48bf9ad6964c/lib/python3.6/_sitebuiltins.py:99:String unnecessarily split in two by black. Please merge them manually..
./asv_bench/env/40d026129f63c107b1ac48bf9ad6964c/lib/python3.6/inspect.py:2768:String unnecessarily split in two by black. Please merge them manually..
./asv_bench/env/40d026129f63c107b1ac48bf9ad6964c/lib/python3.6/inspect.py:2890:String unnecessarily split in two by black. Please merge them manually..

....

This fixes it.

[jreback]

sure