clang-tidy: modernize-use-override (NFC)

Add NOLINT to CommandTestBase due to gmock not adding "override" keyword,
which causes warnings on clang.

wpilibc/src/main/native/include/frc/IterativeRobot.h

@@ -28,7 +28,7 @@ class IterativeRobot : public IterativeRobotBase {
       "Use TimedRobot instead. It's a drop-in replacement that provides more "
       "regular execution periods.")
   IterativeRobot();
-  virtual ~IterativeRobot() = default;
+  ~IterativeRobot() override = default;
 
   /**
    * Provide an alternate "main loop" via StartCompetition().