Fix precision in description file

Author: jeongsoolee09

rule_packages/cpp/Memory1.json

@@ -10,7 +10,7 @@
           "description": "Pointers obtained as result of performing arithmetic should point to an initialized object, or an element right next to the last element of an array.",
           "kind": "path-problem",
           "name": "Pointer arithmetic shall not form an invalid pointer",
-          "precision": "high",
+          "precision": "medium",
           "severity": "error",
           "short_name": "PointerArithmeticFormsAnInvalidPointer",
           "tags": [