Update step-security/harden-runner digest to a90bcbc

Author: renovate[bot]

.github/workflows/codeql.yml

@@ -26,7 +26,7 @@ jobs:
 
     steps:
       - name: Harden Runner
-        uses: step-security/harden-runner@20cf305ff2072d973412fa9b1e3a4f227bda3c76
+        uses: step-security/harden-runner@a90bcbc6539c36a85cdfeb73f7e2f433735f215b
         with:
           egress-policy: audit