Fix sandbox pip runs with new requirements files (take 2)

This reverts commit 4aab0091.

playbooks/roles/edxapp/tasks/deploy.yml

@@ -272,6 +272,7 @@
 
 - name: code sandbox | Install base sandbox requirements and create sandbox virtualenv
   pip:
+    chdir: "{{ edxapp_code_dir }}"
     requirements: "{{ sandbox_base_requirements }}"
     virtualenv: "{{ edxapp_sandbox_venv_dir }}"
     state: present
@@ -283,22 +284,6 @@
     - install
     - install:app-requirements
 
-- name: code sandbox | Install sandbox requirements into sandbox venv
-  shell: "{{ edxapp_sandbox_venv_dir }}/bin/pip install -i {{ COMMON_PYPI_MIRROR_URL }} --exists-action w -r {{ item }}"
-  args:
-    chdir: "{{ edxapp_code_dir }}"
-  with_items:
-    - "{{ sandbox_local_requirements }}"
-    - "{{ sandbox_post_requirements }}"
-  become_user: "{{ edxapp_sandbox_user }}"
-  when: EDXAPP_PYTHON_SANDBOX
-  register: sandbox_install_output
-  changed_when: sandbox_install_output.stdout is defined and 'installed' in sandbox_install_output.stdout
-  tags:
-    - edxapp-sandbox
-    - install
-    - install:app-requirements
-
 - name: code sandbox | put code sandbox into aa-enforce or aa-complain mode, depending on EDXAPP_SANDBOX_ENFORCE
   command: /usr/sbin/{{ edxapp_aa_command }} /etc/apparmor.d/code.sandbox
   when: EDXAPP_PYTHON_SANDBOX