Update and rename Azure Policy - Enforce Explicit Proxy Configuration…

… for Firewall Policies.txt to Azure Policy - Enforce Explicit Proxy Configuration for Firewall Policies.json

Azure Firewall/Policy - Azure Policy Definitions/Policy - Enforce Explicit Proxy Configuration for Firewall Policies/Azure Policy - Enforce Explicit Proxy Configuration for Firewall Policies.txt → Azure Firewall/Policy - Azure Policy Definitions/Policy - Enforce Explicit Proxy Configuration for Firewall Policies/Azure Policy - Enforce Explicit Proxy Configuration for Firewall Policies.json

@@ -31,4 +31,4 @@
       "defaultValue": "Audit"
     }
   }
-}
+}