attributes/default.rb: bump default['docker_compose']['release'] to 1.21.2
attributes/default.rb: bump default['docker_compose']['release'] to 1.21.2

Signed-off-by: Florian Klink <358221512ff61c576dd49172149e4a48454cce92@flokli.de>

sboschert/chef-cookbook-docker_compose