GitHub SSH public key missing from `test-ibm-rhel8_arm_cross_container-x64-1` about build HOT 4 OPEN

In https://ci.nodejs.org/job/node-cross-compile/configure there's some scripting that's supposed to add to the known_hosts:

grep -q ^$TEMP_REPO_SERVER ~/.ssh/known_hosts || (ssh-keyscan -t rsa $TEMP_REPO_SERVER >> ~/.ssh/known_hosts)

but looking at, e.g. https://ci.nodejs.org/job/node-cross-compile/nodes=cross-compiler-rhel8-armv7-gcc-10-glibc-2.28/47396/console, the attempt to git checkout is happening before that script is run.

I've manually added the key to the known_hosts file -- we're going to have to update it again when we migrate the tmp binary git repository from Equinix Metal (#3597).

from build.

Done the same for test-digitalocean-rhel8_arm_cross_container-x64-2.

from build.