Pass StringRef by value instead of by const-ref

src/catch2/internal/catch_combined_tu.cpp

@@ -194,7 +194,7 @@ Catch::LeakDetector::~LeakDetector() {
 
 namespace Catch {
 
-    MessageInfo::MessageInfo(   StringRef const& _macroName,
+    MessageInfo::MessageInfo(   StringRef _macroName,
                                 SourceLineInfo const& _lineInfo,
                                 ResultWas::OfType _type )
     :   macroName( _macroName ),

src/catch2/internal/catch_message_info.hpp

@@ -17,7 +17,7 @@
 namespace Catch {
 
     struct MessageInfo {
-        MessageInfo(    StringRef const& _macroName,
+        MessageInfo(    StringRef _macroName,
                         SourceLineInfo const& _lineInfo,
                         ResultWas::OfType _type );