Remove override of "patch" function

Overriding the patch method with an incompatable argument
list breaks contrib tests that used the version from
TestCase. This method was introduced in commit
3eda05a9b0b69803a0269f2aa344d14e5823bf6d but removing this
method does not affect other tests.

Change-Id: Iaecd171e5a548b2843b46e7c4b8ef48c52af6db6
Closes-Bug: 1263241
Enable parallel while deleting neutron resources

The confirm delete task was run immediately after creation in
handle_delete, which blocked the whole DependencyTaskGroup.
This patch gives other delete jobs a chance to run by stepping
the delete task in check_delete_complete.

Change-Id: I9ced21d3f98d949bd099bead27ac7b3e2d1090de
Merge "Enable parallel while deleting neutron resources"
Merge "Remove override of "patch" function"