Run check-sarif Action using Node 16

`using: node12` Actions have already been running using Node 16 for
some time.

Author: henrymercer

.github/actions/check-sarif/action.yml

@@ -16,5 +16,5 @@ inputs:
       Comma separated list of query ids that should NOT be included in this SARIF file.
 
 runs:
-  using: node12
+  using: node16
   main: index.js