fix typo

Co-authored-by: Esben Sparre Andreasen <esbena@github.com>

Author: erik-krogh

javascript/ql/src/Security/CWE-094/UnsafeCodeConstruction.ql

@@ -4,7 +4,7 @@
  *              user to execute arbitrary code.
  * @kind path-problem
  * @problem.severity warning
- * @precision warning
+ * @precision medium
  * @id js/unsafe-code-construction
  * @tags security
  *       external/cwe/cwe-094