Enable log macros to work with no args (#4475)

This is enabled by the C++20 __VA_OPT__ feature.
Uses of "{}" format string were updated.
Some warning suppressions were required for older clang versions.
Also improve codegen of wpi::Logger::Log(), frc::ReportError(), and frc::MakeError();
these generate better and less redundant code if they use fmt::string_view for the
format string instead of templating on it.

wpilibc/src/main/native/cpp/DriverStation.cpp

@@ -635,7 +635,7 @@ double DriverStation::GetMatchTime() {
 double DriverStation::GetBatteryVoltage() {
   int32_t status = 0;
   double voltage = HAL_GetVinVoltage(&status);
-  FRC_CheckErrorStatus(status, "{}", "getVinVoltage");
+  FRC_CheckErrorStatus(status, "getVinVoltage");
 
   return voltage;
 }