Go: note that numeric-typed nodes can't cause path traversal

Author: smowton

go/ql/lib/semmle/go/security/TaintedPathCustomizations.qll

@@ -70,6 +70,15 @@ module TaintedPath {
     PathAsSink() { this = any(FileSystemAccess fsa).getAPathArgument() }
   }
 
+  /**
+   * A numeric-typed node, considered a sanitizer for path traversal.
+   */
+  class NumericSanitizer extends Sanitizer {
+    NumericSanitizer() {
+      this.getType() instanceof NumericType or this.getType() instanceof BoolType
+    }
+  }
+
   /**
    * A call to `filepath.Rel`, considered as a sanitizer for path traversal.
    */