Fix molecule env download from url

By default, if the file exists locally, get_url will NOT download the
file.
force shall be set to true to force the file to be downloaded.

tasks/create_conda_env.yml

@@ -18,6 +18,7 @@
   get_url:
     url: "{{ env_file }}"
     dest: "{{ env_file_path }}"
+    force: true
     owner: conda
     group: users
     mode: 0644