CI: Remove obsolete reverse shell historically used to debug CI

This reverse shell was historically used to debug CI jobs interactively.
It is not used anymore, and may be causing jobs to hang, then timeout.
There is no reason to keep it, and removing it simplifies CI jobs.

Additionally it has been reported as flagged by security scanners, so
removing it makes Mitogen easier to package/adopt.

fixes #847

(cherry picked from commit a990eb3)

Author: moreati

.ci/azure-pipelines-steps.yml

@@ -37,9 +37,6 @@ steps:
 
   displayName: activate venv
 
-- script: .ci/spawn_reverse_shell.py
-  displayName: "Spawn reverse shell"
-
 - script: .ci/$(MODE)_install.py
   displayName: "Run $(MODE)_install.py"
 

.ci/spawn_reverse_shell.py

@@ -31,6 +31,7 @@ v0.2.10 (unreleased)
 * :gh:issue:`758` fix initilialisation of callback plugins in test suite, to address a `KeyError` in
   :method:`ansible.plugins.callback.CallbackBase.v2_runner_on_start`
 * :gh:issue:`775` Add msvcrt to the default module deny list
+* :gh:issue:`847` Removed historic Continuous Integration reverse shell
 
 
 v0.2.9 (2019-11-02)