envvars-api: bump to 0.0.64-20241220145144-0b848d21
From 0.0.63-20241204134340-d383083d To 0.0.64-20241220145144-0b848d21 See https://gitlab.wikimedia.org/repos/cloud/toolforge/envvars-api/-/releases
Signed-off-by: Slavina Stefanova sstefanova@wikimedia.org