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/include/frc/RobotBase.h

@@ -34,7 +34,7 @@ void RunRobot(wpi::mutex& m, Robot** robot) {
   } catch (const frc::RuntimeError& e) {
     e.Report();
     FRC_ReportError(
-        err::Error, "{}",
+        err::Error,
         "The robot program quit unexpectedly."
         " This is usually due to a code error.\n"
         "  The above stacktrace can help determine where the error occurred.\n"