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 15 minutes and 56 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Test
passed #117046
amd64
dispatcher-debian-10

00:02:20

passed #117048
amd64
dispatcher-debian-11

00:02:53

passed #117047
amd64
server-debian-10

00:03:02

passed #117049
amd64
server-debian-11

00:04:59

 
  Analyze
passed #117050
amd64-dind
bandit-sast

00:00:53

passed #117051
amd64
black

00:00:34

passed #117052
amd64
code_quality

00:00:21

passed #117057
amd64
codespell

00:00:20

passed #117053
amd64
coverage

00:06:50

60.88%
passed #117054
amd64
dockerfiles

00:00:16

passed #117056
amd64
pylint

00:03:05

passed #117055
amd64
schemas

00:00:31

 
  Build
passed #117059
amd64
debian/10

00:01:23

passed #117058
amd64
doc

00:00:52

passed #117060
amd64-dind
docker-amd64-dispatcher

00:03:39

passed #117061
amd64-dind
docker-amd64-server

00:04:03