Merge topic 'fix-IMPORTED-GLOBAL-reconfigure'

5ff7587 Initialize IMPORTED GLOBAL targets on reconfigure (#13702)

Source/cmGlobalGenerator.cxx

@@ -828,6 +828,7 @@ void cmGlobalGenerator::Configure()
   this->LocalGenerators.clear();
   this->TargetDependencies.clear();
   this->TotalTargets.clear();
+  this->ImportedTargets.clear();
   this->LocalGeneratorToTargetMap.clear();
   this->ProjectMap.clear();
   this->RuleHashes.clear();