speed up check_duplicates and reduce ram usage

[virophagesp]

previously indexs were being added to a list and then its only use was to get the length I have changed the code to instead have it be a number

Related Issue/Addition to code

• Addition to code.

Proposed Changes

• replace check_duplicate's list with set
• change domains list so every element has a dot in front

Why is this change needed?

It speeds up the checking of duplicate comments ### Additional Info - the only time the list is used other than when being added is having its length checked ### Checklist: - [x] My code follows the style guidelines of this project and I have read [CONTRIBUTING.md](/CONTRIBUTING.md) - [x] I have performed a self-review of my own code - [x] I have commented my code, particularly in hard-to-understand areas - [x] I have made corresponding changes to the documentation - [x] My changes generate no new warnings - [x] Any dependent changes have been merged and published in downstream modules - [x] I have checked my code and corrected any misspellings

[virophagesp]

this is ready @ThioJoe

[virophagesp]

I should have mentioned I thought I could add labels in draft mode, I could not

[virophagesp]

this is stale