kaniko: use stretch and install git.

1 job for master in 3 minutes and 48 seconds (queued for 3 seconds)
Status Job ID Name Coverage
failed #241217


Name Stage Failure
build Build
1 upgraded, 32 newly installed, 0 to remove and 0 not upgraded.
Need to get 16.2 MB of archives.
After this operation, 77.5 MB of additional disk space will be used.
Do you want to continue? [Y/n] Abort.
The command '/bin/sh -c apt-get update && apt-get install --no-install-suggests --no-install-recommends git && apt-get clean -y && rm -rf /var/lib/apt/lists/*' returned a non-zero code: 1
make: Leaving directory '/builds/videolan/docker-images-aarch64/videolan-kaniko'
make: *** [../common.mak:11: build] Error 1
ERROR: Job failed: exit code 2