Some template instantiation reductions

src/catch2/internal/catch_reporter_spec_parser.cpp

@@ -21,9 +21,9 @@ namespace Catch {
         };
 
         kvPair splitKVPair(StringRef kvString) {
-            auto splitPos = static_cast<size_t>( std::distance(
-                kvString.begin(),
-                std::find( kvString.begin(), kvString.end(), '=' ) ) );
+            auto splitPos = static_cast<size_t>(
+                std::find( kvString.begin(), kvString.end(), '=' ) -
+                kvString.begin() );
 
             return { kvString.substr( 0, splitPos ),
                      kvString.substr( splitPos + 1, kvString.size() ) };