CodeGen from PR 21069 in Azure/azure-rest-api-specs

Scrub custom-words.txt for non-words and descriptions for more inclusive terminology (Azure#21069)

* Delete term AADP from custom-words as its not a commonly known acronym.

* Delete term 'accountid' from custom-words.txt. You should use proper casing and spacing according to context, such as 'AccountId', 'accountId', 'accountID', 'account ID', or so on, instead.

* Delete a whole lot of terms that don't seem to be used anywhere in the specification folder according to a cursory search.

* Delete many duplicates from custom-words.txt

* Use cSpell.json to quarantine away some misspelled words from custom-words.txt. And remove duplicates of PPSX and PPTM.

* 'Mwarev' should not be a word. Terms like 'VMwarevSphere' 'vmware', 'vSphere' should be words instead.

* Using cSpell and custom-words better. 'targetv' should not be a custom word in order to allow 'targetvCenterId'.

* Actually remove UNKNOWON from custom-words now that it has a cSpell.json exception.

* Updation is not a real word.

* Sort 'vcenters'

* Expand away the nonstandard capitalized acronym Vrops from old documentation,

* Noreuse isn't a proper word, so making it a cSpell exception.

* Sort 'cadl'

* Retire some references to whitelists from documentation.

* Replace */* with **