Add code sharing sample (#1444)

* code-sharing boilerplate

* initial commit of code-sharing logic

* documentation improvements

* added code-sharing to samples.yaml

* Updated counter UI to visually indicate communication with the server

* added code_sharing to CI

* CI changes to code_sharing

* fixed test with DI

* formatting

* added shared module to CI

* adds forgotten CI change

code_sharing/docker-compose.yml

@@ -0,0 +1,11 @@
+version: "3.7"
+services:
+  server:
+    build:
+      context: server
+    ports:
+      - 8080:8080
+    environment:
+      SERVER_PORT: "8080"
+      SERVER_URL: "localhost"
+      SERVER_SCHEME: "http"