Remove pip_required_pip_packages var and related tasks

The pip_required_pip_packages variable was introduced in
order to facilitate installing extra packages required
for SNI support. In Pike these extra package installs
were removed due to interference with distribution
packages installed, and the distro package installation
for this support was deemed better.

This variable and the related tasks therefore no longer
server any function and should be removed.

Change-Id: I76fb9ae324ff69e8fc8b23f7b610d2aca48d0949

defaults/main.yml

@@ -50,8 +50,6 @@ pip_packages:
   - setuptools
   - wheel
 
-pip_required_pip_packages: []
-
 ## APT Cache options
 cache_timeout: 600
 

releasenotes/notes/remove-required-pip-packages-49a4215bdddea189.yaml

@@ -0,0 +1,5 @@
+---
+deprecations:
+  - |
+    The variable ``pip_required_pip_packages`` has been removed as it is not
+    used and not required.

tasks/install_source.yml

@@ -36,30 +36,3 @@
       until: pip_install_fall_back | success
       retries: 3
       delay: 2
-
-- block:
-    - name: Install pip packages
-      pip:
-        name: "{{ pip_required_pip_packages | map('quote') | join(' ') }}"
-        state: "{{ pip_install_package_state }}"
-        extra_args: >-
-          {{ (pip_install_upper_constraints is defined) | ternary('--constraint ' + pip_install_upper_constraints | default(''),'') }}
-          {{ pip_install_options }}
-      register: install_packages
-      until: install_packages | success
-      retries: 5
-      delay: 2
-
-  rescue:
-    - name: Install pip packages (fall back mode)
-      pip:
-        name: "{{ pip_required_pip_packages | map('quote') | join(' ') }}"
-        state: "{{ pip_install_package_state }}"
-        extra_args: >-
-          --isolated
-          {{ (pip_install_upper_constraints is defined) | ternary('--constraint ' + pip_install_upper_constraints | default(''),'') }}
-          {{ pip_install_options }}
-      register: install_packages_fall_back
-      until: install_packages_fall_back | success
-      retries: 5
-      delay: 2