Fix indentation in docker-compose.*.yaml files #94 (#96)

Wrong indentation causes error

Author: mkutyba

docker-compose.dev.yml

@@ -2,5 +2,5 @@ version: "2"
 services:
   boilerplate-api:
     command: yarn dev -- -L
-  environment:
-    - NODE_ENV=development
+    environment:
+      - NODE_ENV=development

docker-compose.prod.yml

@@ -2,5 +2,5 @@ version: "2"
 services:
   boilerplate-api:
     command: yarn start
-  environment:
-    - NODE_ENV=production
+    environment:
+      - NODE_ENV=production