fix: return full authorization header in unsupported authorization type error

the unsupported authorization type error only echoed the algorithm back in ArgumentValue, while s3 returns the whole Authorization header there. the parse error now carries the raw header and the s3 error mapping uses it, which also lets the bats test skipped for #1705 run again.

Fixes #2489

tests/integration/sigv4_auth.go

@@ -65,7 +65,7 @@ func Authentication_unsupported_signature_version(s *S3Conf) error {
 			return err
 		}
 
-		return checkHTTPResponseApiErr(resp, s3err.GetInvalidArgumentErr(s3err.InvalidArgAuthorizationType, "AWS2-HMAC-SHA1"))
+		return checkHTTPResponseApiErr(resp, s3err.GetInvalidArgumentErr(s3err.InvalidArgAuthorizationType, authHdr))
 	})
 }