Fix route guide tutorial (#2094)

We changed some APIs and the tutorial code snippets have to be updated.

Sources/GRPCCore/Documentation.docc/Tutorials/Route-Guide/Resources/route-guide-sec06-step03-create-client.swift

@@ -5,7 +5,7 @@ extension RouteGuide {
     let client = try GRPCClient(
       transport: .http2NIOPosix(
         target: .ipv4(host: "127.0.0.1", port: 31415),
-        config: .defaults()
+        config: .defaults(transportSecurity: .plaintext)
       )
     )
   }

Sources/GRPCCore/Documentation.docc/Tutorials/Route-Guide/Resources/route-guide-sec06-step04-run-client.swift

@@ -5,7 +5,7 @@ extension RouteGuide {
     let client = try GRPCClient(
       transport: .http2NIOPosix(
         target: .ipv4(host: "127.0.0.1", port: 31415),
-        config: .defaults()
+        config: .defaults(transportSecurity: .plaintext)
       )
     )
 

Sources/GRPCCore/Documentation.docc/Tutorials/Route-Guide/Resources/route-guide-sec06-step05-stub.swift

@@ -5,7 +5,7 @@ extension RouteGuide {
     let client = try GRPCClient(
       transport: .http2NIOPosix(
         target: .ipv4(host: "127.0.0.1", port: 31415),
-        config: .defaults()
+        config: .defaults(transportSecurity: .plaintext)
       )
     )
 

Sources/GRPCCore/Documentation.docc/Tutorials/Route-Guide/Resources/route-guide-sec06-step06-get-feature.swift

@@ -5,7 +5,7 @@ extension RouteGuide {
     let client = try GRPCClient(
       transport: .http2NIOPosix(
         target: .ipv4(host: "127.0.0.1", port: 31415),
-        config: .defaults()
+        config: .defaults(transportSecurity: .plaintext)
       )
     )
 

Sources/GRPCCore/Documentation.docc/Tutorials/Route-Guide/Resources/route-guide-sec06-step07-list-features.swift

@@ -5,7 +5,7 @@ extension RouteGuide {
     let client = try GRPCClient(
       transport: .http2NIOPosix(
         target: .ipv4(host: "127.0.0.1", port: 31415),
-        config: .defaults()
+        config: .defaults(transportSecurity: .plaintext)
       )
     )
 

Sources/GRPCCore/Documentation.docc/Tutorials/Route-Guide/Resources/route-guide-sec06-step08-record-route.swift

@@ -5,7 +5,7 @@ extension RouteGuide {
     let client = try GRPCClient(
       transport: .http2NIOPosix(
         target: .ipv4(host: "127.0.0.1", port: 31415),
-        config: .defaults()
+        config: .defaults(transportSecurity: .plaintext)
       )
     )
 

Sources/GRPCCore/Documentation.docc/Tutorials/Route-Guide/Resources/route-guide-sec06-step09-route-chat.swift

@@ -5,7 +5,7 @@ extension RouteGuide {
     let client = try GRPCClient(
       transport: .http2NIOPosix(
         target: .ipv4(host: "127.0.0.1", port: 31415),
-        config: .defaults()
+        config: .defaults(transportSecurity: .plaintext)
       )
     )