AK: Display SourceLocation function name in color

It's much easier to spot the function name (which is what you often
expect) like this.

AK/SourceLocation.h

@@ -45,7 +45,7 @@ template<>
 struct AK::Formatter<AK::SourceLocation> : AK::Formatter<FormatString> {
     ErrorOr<void> format(FormatBuilder& builder, AK::SourceLocation location)
     {
-        return AK::Formatter<FormatString>::format(builder, "[{} @ {}:{}]", location.function_name(), location.filename(), location.line_number());
+        return AK::Formatter<FormatString>::format(builder, "[\x1b[34m{}\x1b[0m @ {}:{}]", location.function_name(), location.filename(), location.line_number());
     }
 };