docs: add listenV4 and listenV6 config examples

Author: aramalipoor

cmd/erpc/main_test.go

@@ -43,6 +43,7 @@ logLevel: DEBUG
 
 server:
   httpHostV4: "` + localHost + `"
+  listenV4: true
   httpPort: ` + localPort + `
 `)
 

docs/pages/config/database.mdx

@@ -7,7 +7,9 @@ Long-term storage is optional but used for various purposes such as caching, rat
 ```yaml filename="erpc.yaml"
 # ...
 database:
-  evmJsonRpcCache: # ...
+  evmJsonRpcCache:
+    driver: memory | redis | postgresql | dynamodb
+    # ... (driver specific config, see below)
 ```
 
 ### `evmJsonRpcCache`

docs/pages/config/example.mdx

@@ -69,14 +69,18 @@ database:
 
 # The main server for eRPC to listen for requests.
 server:
+  listenV4: true
   httpHostV4: "0.0.0.0"
+  listenV6: false
   httpHostV6: "[::]"
   httpPort: 4000
 
 # Optional Prometheus metrics server.
 metrics:
   enabled: true
+  listenV4: true
   hostV4: "0.0.0.0"
+  listenV6: false
   hostV6: "[::]"
   port: 4001