[fix] Share /var/lib/awx/projects between awx-task and awx-receptor

Moves the needle from “inventory jobs fail because they can't find anything,” to “inventory jobs fail with a Python stack trace” (for want of an `oc` binary in `$PATH`).

In hindsight, it's pretty clear that if `awx-task` expects to be able to fiddle with `/etc/receptor/receptor.conf`, the two processes are supposed to run from the same container. Oh well...

Here is what I could figure out from the relics left behind under `awx_verbose = true` and the previous commit:

- For inventory jobs (unlike SCM jobs), `receptor` creates pods and feeds them some bizarre mix of JSON and base64-encoded ZIP files onto their stdin. Said pods are supposed to unpack and run same, and report back using a similar format.
- Manual inspection of the input ZIP file for a failed inventory job, showed that said ZIP file contained a `project/` subdirectory that was empty.
- From the fact that this here commit actually works, we deduce that `awx-task` cherry-picks stuff from `/var/lib/awx/projects` to fill the ZIP, sends same through `receptorctl`, `receptor` on the other side runs a Kubernetes pod as per above, and the `stdout` thereof flows the opposite way. Although I would be quite incapable of providing chapter and verse for these, either in the source code or the documentation...

Author: Dominique Quatravaux

Diff for: ansible/roles/awx-instance/tasks/k8s.yml

@@ -200,6 +200,10 @@
             # same config file:
             - name: receptor-bogus-conf
               mountPath: /etc/receptor
+            # Conversely, awx-task expects to “see” projects here
+            # after awx-receptor pulls them from SCM:
+            - name: var-lib-awx-projects
+              mountPath: /var/lib/awx/projects
             - name: receptor-sock
               mountPath: "{{ awx_receptor_socket_path | dirname }}"
             env:
@@ -223,6 +227,8 @@
               mountPath: /etc/receptor
             - name: receptor-sock
               mountPath: "{{ awx_receptor_socket_path | dirname }}"
+            - name: var-lib-awx-projects
+              mountPath: /var/lib/awx/projects
           #####################################################
           - name: awx-redis
             image: "{{ awx_redis_image_mirrored_to }}"
@@ -296,6 +302,8 @@
                 path: receptor.conf
           - name: receptor-sock
             emptyDir: {}
+          - name: var-lib-awx-projects
+            emptyDir: {}
   notify: Restart AWX pod
 
 - meta: flush_handlers