fix: cleanup TAPCollectorAuthorizationAlreadyRevoked

[matiasedgeandnode]

This PR simply cleans up what's already there, but if you would consider a slightly bigger re-write, maybe the collector would benefit from a modifier onlyAuthorized(address _signer) for thawSigner, cancelThawSigner and revokeAuthorizedSigner like what's proposed by #1085 -> here.

[openzeppelin-code]

fix: cleanup TAPCollectorAuthorizationAlreadyRevoked

Generated at commit: 80fa1b02bc5ddb0dd0ada53d41e79c580c232ccd

🚨 Report Summary

	Severity Level	Results
Contracts	Critical High Medium Low Note Total	2 5 0 15 39 61
Dependencies	Critical High Medium Low Note Total	0 0 0 0 0 0

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For more details view the full report in OpenZeppelin Code Inspector

[tmigone]

I like what you did with Authorizable! Want to PR it into horizon?

[matiasedgeandnode]

Please look at #1110 instead.