Create test for bad pluralization

What does this MR do?

Attempts to test for words that are improperly pluralized with a (s) construction. Increased difficulty from:

• should be case-insensitive
• should ignore HTTP(S), which is a valid and common construction

https://stackoverflow.com/questions/2973436/regex-lookahead-lookbehind-and-atomic-groups helped tremendously, especially this part:

(?!) - negative lookahead
(?=) - positive lookahead
(?<=) - positive lookbehind
(?<!) - negative lookbehind

(?>) - atomic group

Related issues

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