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/counter/Tachometer.cpp

@@ -19,7 +19,7 @@ Tachometer::Tachometer(DigitalSource& source)
     : Tachometer({&source, wpi::NullDeleter<DigitalSource>()}) {}
 Tachometer::Tachometer(std::shared_ptr<DigitalSource> source) {
   if (source == nullptr) {
-    throw FRC_MakeError(err::NullParameter, "{}", "source");
+    throw FRC_MakeError(err::NullParameter, "source");
   }
 
   m_source = source;