Fix rubocop cautions

lib/googleauth/compute_engine.rb

@@ -98,7 +98,8 @@ END
           when 404
             raise(Signet::AuthorizationError, NO_METADATA_SERVER_ERROR)
           else
-            msg = "Unexpected error code #{resp.status}" + UNEXPECTED_ERROR_SUFFIX
+            msg = "Unexpected error code #{resp.status}" \
+              "#{UNEXPECTED_ERROR_SUFFIX}"
             raise(Signet::AuthorizationError, msg)
           end
         end

lib/googleauth/signet.rb

@@ -84,7 +84,9 @@ module Signet
         begin
           yield
         rescue => e
-          raise e if e.is_a?(Signet::AuthorizationError) || e.is_a?(Signet::ParseError)
+          if e.is_a?(Signet::AuthorizationError) || e.is_a?(Signet::ParseError)
+            raise e
+          end
 
           if retry_count < max_retry_count
             retry_count += 1