Simplify docker-compose file

Author: darthjee

docker-compose.yml

@@ -1,18 +1,9 @@
 version: '3'
 services:
-  base: &base
-    image: ruby_gnuplot
-    working_dir: /home/gnuplot/gnuplot
-    volumes:
-      - .:/home/gnuplot/gnuplot
-
-  base_build:
-    <<: *base
-    build: .
-    command: echo done
-
   ruby_gnuplot:
-    <<: *base
+    build: .
+    working_dir: /home/gnuplot/gnuplot
     container_name: ruby_gnuplot
-    depends_on: [base_build]
     command: /bin/bash
+    volumes:
+      - .:/home/gnuplot/gnuplot