Mark array arguments to find operators as read-only

[foxymiles]

Description of change

Mark the array arguments to find operators like In and ArrayContains as readonly. This makes it possible to use them with readonly arrays as parameters without casting or having to make copies.

Pull-Request Checklist

• Code is up-to-date with the master branch
• npm run format to apply prettier formatting
• npm run test passes with this change
• This pull request links relevant issues as Fixes #0000 N/A
• There are new or updated unit tests validating the change N/A
• Documentation has been updated to reflect this change N/A
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