Make Integrations (shared) codeowners of proto/ (#4576)

The integrations team should codeown all the protobuf stuff, because they own the integrations that consume the message definitions. (config.proto is a borderline case, but that's a borderline case for every team, so this solution isn't worse than any other.)

Author: rosecodym

CODEOWNERS

@@ -27,7 +27,7 @@ pkg/giturl/ @trufflesecurity/Scanning  @trufflesecurity/OSS
 pkg/handlers/ @trufflesecurity/Scanning  @trufflesecurity/OSS
 pkg/iobuf/ @trufflesecurity/Scanning  @trufflesecurity/OSS
 pkg/sanitizer/ @trufflesecurity/Scanning  @trufflesecurity/OSS
-proto/ @trufflesecurity/Scanning  @trufflesecurity/OSS
+proto/ @trufflesecurity/Scanning  @trufflesecurity/Integrations
 
 # OSS
 pkg/detectors/ @trufflesecurity/OSS