Change egress policy from audit to block (#1086)

Author: AshleyDumaine

.github/workflows/build-push.yml

@@ -19,7 +19,7 @@ jobs:
         uses: step-security/harden-runner@a5ad31d6a139d249332a2605b85202e8c0b78450 # v2.19.1
         with:
           disable-sudo: true
-          egress-policy: audit
+          egress-policy: block
           allowed-endpoints: >
             api.github.com:443
             github.com:443