[clang][dataflow] Fix a missing break from a switch case -Wimplicit-fallthrough (llvm#120739)

Missed when changing code in
llvm#120102

Author: jvoung

clang/lib/Analysis/FlowSensitive/SmartPointerAccessorCaching.cpp

@@ -71,7 +71,7 @@ bool hasSmartPointerClassShape(const CXXRecordDecl &RD, bool &HasGet,
                                 ->getCanonicalTypeUnqualified();
         }
       }
-    }
+    } break;
     default:
       break;
     }