nginx-golang fix some minor typos (#49)

change mysql version in readme to match compose file

Signed-off-by: Charlie Arehart <charlie@carehart.org>

nginx-golang-mysql/README.md

@@ -24,7 +24,7 @@ services:
     build: backend
     ...
   db:
-    image: mysql:5.7
+    image: mysql:8.0.19
     ...
   proxy:
     build: proxy

nginx-golang/README.md

@@ -21,13 +21,15 @@ services:
   frontend:
     build: frontend
     ports:
-    - 80:80
+      - 80:80
+    depends_on:
+      - backend
   backend:
     build: backend
 ```
 The compose file defines an application with two services `frontend` and `backend`.
 When deploying the application, docker-compose maps port 80 of the frontend service container to the same port of the host as specified in the file.
-Make sure port 80 on the host is not already being in use.
+Make sure port 80 on the host is not already in use.
 
 ## Deploy with docker-compose