Unset any custom TRUE or FALSE macros, should they be defined.

This is necessary on macOS 11, as system headers on that OS do
define these macros for some weird reason.

Reconstruction/Jet/JetUncertainties/JetUncertainties/UncertaintyEnum.h

@@ -91,7 +91,7 @@ namespace CompScaleVar
     {
         // Error state
         UNKNOWN=0,      // Failure/unset/etc
-        
+
         // Scale uncertainties
         FourVec,        // The full jet 4-vector
         Pt,             // The jet pT
@@ -106,7 +106,7 @@ namespace CompScaleVar
         C2Beta1,        // The value of C_2^{beta=1} (ECF ratio)
         Qw,             // The value of Qw
         TagScaleFactor, // Tagging efficiency SF
-        
+
         // Resolution uncertainties
         MassRes,        // The jet mass resolution, relative
         MassResAbs,     // The jet mass resolution, absolute
@@ -212,6 +212,14 @@ namespace JetTopology
     TypeEnum stringToEnum(const TString type);
 }
 
+// Unset the TRUE and FALSE macros, defined in a custom way on macOS 11.
+#ifdef TRUE
+#  undef TRUE
+#endif
+#ifdef FALSE
+#  undef FALSE
+#endif
+
 namespace ExtendedBool
 {
     enum TypeEnum