Upload action

Adding upload action that can run after all pipeline steps, but before
cleanup. Allows test writers to run commands in a docker image of
choice, with the artifacts mounted in.

FVP action updated to allow saving things to the artifact directory.
Other actions could also use this simply by saving to that location.

Change-Id: I11043065d4221b7732a25a3e91b73a58a11f00ea
Signed-off-by: Dean Birch <dean.birch@arm.com>
16 jobs for fvp_file_upload in 17 minutes and 36 seconds (queued for 3 seconds)
latest
Status Job ID Name Coverage
  Test
passed #115842
amd64
dispatcher-debian-10

00:03:54

passed #115844
amd64
dispatcher-debian-11

00:06:11

passed #115843
amd64
server-debian-10

00:04:36

passed #115845
amd64
server-debian-11

00:06:52

 
  Analyze
passed #115846
amd64-dind
bandit-sast

00:00:58

passed #115847
amd64
black

00:00:37

passed #115848
amd64
code_quality

00:00:25

passed #115853
amd64
codespell

00:00:21

passed #115849
amd64
coverage

00:06:32

60.85%
passed #115850
amd64
dockerfiles

00:00:19

passed #115852
amd64
pylint

00:03:07

passed #115851
amd64
schemas

00:00:33

 
  Build
passed #115855
amd64
debian/10

00:01:17

passed #115854
amd64
doc

00:00:36

passed #115856
amd64-dind
docker-amd64-dispatcher

00:03:46

passed #115857
amd64-dind
docker-amd64-server

00:04:09