Update signature work score description

tips/TIP-0045/tip-0045.md

@@ -1152,7 +1152,7 @@ Let the work score of a transaction be defined as follows.
 - Let `Allotment Score` be `Work Score Parameters::Allotment * Allotments Count`.
 - Let `Signature Score` be the sum of work scores of the signatures contained in _Signature Unlocks_ (directly or within
   _Multi Unlocks_) within `Unlocks`.
-  - Signature work scores are defined in [TIP-46 (Work Score)](../TIP-0046/tip-0046.md#work-score-1).
+  - Signature work scores are defined with the respective schema definition.
 - Return `Size Score + Input Score + Context Input Score + Outputs Score + Allotment Score + Signature Score`.
 
 ## Validation