Remove pip_install as meta-dependency

The repo_server role does no pip installations - they're all done
in the repo_build role.

This removes the unnecessary dependency.

Note that the httplib2 pip install task is removed as Ansible 2.x
no longer requires it.

Related-Bug: #1633105
Change-Id: I4a2ff6c6e5cd40d87d4218f63c09e96da82da1aa

meta/main.yml

@@ -36,4 +36,3 @@ dependencies:
   - role: apt_package_pinning
     when:
       - ansible_pkg_mgr == 'apt'
-  - pip_install

tests/test-repo-server-functional.yml

@@ -17,9 +17,6 @@
   hosts: repo_all
   user: root
   tasks:
-    - name: Install httplib2 so we can use the uri module
-      pip:
-        name: httplib2
     - name: Check nginx is running
       shell: "ps auxf | grep nginx"
       register: ps_auxf_nginx