gitlab-ci: add python3-requests to the test-vk container

gitlab-ci: add python3-requests to the test-vk container

After 90a39af5f65 ("ci: Drop the git dependency in tracie"), we have
this error in the radv-polaris10-traces job:

"
...

+ /builds/tanty/mesa/artifacts/tracie/tests/test.sh
tracie_succeeds_if_all_images_match: Fail
Traceback (most recent call last):
  File "/tmp/tracie.test.glY0O23HJo/tracie.py", line 6, in <module>
    import requests
ModuleNotFoundError: No module named 'requests'

...
"

v2:
  - Updated commit log to be more descriptive (Michel).

Fixes: 90a39af5f65 ("ci: Drop the git dependency in tracie")
Signed-off-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Alexandros Frantzis <alexandros.frantzis@collabora.com>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4237>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4237>