[ci] Move pip commands to run cmd for cross-arch tests

This adds more transparency to the command, and reduces the responsibility
of the cross-arch image.

Also, the `pip freeze` command is now run after installing nox's
dependencies.

Signed-off-by: Tiyash Basu <[email protected]>

Author: tiyash-basu-frequenz

.github/containers/nox-cross-arch/entrypoint.bash

@@ -4,7 +4,4 @@ set -e
 echo "System details:" $(uname -a)
 echo "Machine:" $(uname -m)
 
-pip install -e .[dev-noxfile]
-pip freeze
-
 exec "$@"

.github/workflows/ci.yaml

@@ -164,7 +164,7 @@ jobs:
             --net=host \
             --platform linux/${{ matrix.arch }} \
             localhost/nox-cross-arch:latest \
-            nox -e ${{ matrix.nox-session }}
+            bash -c "pip install -e .[dev-noxfile]; nox --install-only -e ${{ matrix.nox-session }}; pip freeze; nox -e ${{ matrix.nox-session }}"
         timeout-minutes: 30
 
       # This ensures that the runner has access to the pip cache.