Add security tag for missing-actions-permissions

This ensures that it will remain in the default suite.

Author: Dave Bartolomeo

actions/ql/src/Security/CWE-275/MissingActionsPermissions.ql

@@ -3,11 +3,12 @@
  * @description Workflows should contain permissions to provide a clear understanding has permissions to run the workflow.
  * @kind problem
  * @security-severity 5.0
- * @problem.severity recommendation
+ * @problem.severity warning
  * @precision high
  * @id actions/missing-workflow-permissions
  * @tags actions
  *       maintainability
+ *       security
  *       external/cwe/cwe-275
  */