Revert "Remove changes to image squashing"

This reverts commit d166e63.

Author: thejsj

ansible/roles/squash_image/tasks/main.yml

@@ -1,10 +1,15 @@
 ---
+- name: squash newly created image
+  become: true
+  ignore_errors: true # Might already be squashed
+  shell: docker-squash "{{ unsquahed_image_id.stdout_lines[0] }}" -t "{{ container_image }}:{{ container_tag }}"
+
 - name: get image id for newly created image
   become: true
-  shell: docker images -a | grep "{{ container_image }}" --color=never | awk '{print $3}'
+  shell: docker images -a | grep "{{ container_image }}" | grep "{{ container_tag }}" | awk '{print $3}'
   register: unsquahed_image_id
 
 - name: squash newly created image
   become: true
   ignore_errors: true # Might already be squashed
-  shell: docker-squash "{{ unsquahed_image_id.stdout }}" -t "{{ container_image }}:{{ container_tag }}"
+  shell: docker-squash "{{ unsquahed_image_id.stdout_lines[0] }}" -t "{{ container_image }}:{{ container_tag }}"