Test by compiling sample contracts

Add two simple contracts (cairo0 and cairo1) and assert they can be compiled.

Can be done in this section of the shell script, perhaps after checking the versions:
https://github.com/Shard-Labs/cairo-cli-docker/blob/7cc3a832e99e28b9f136ab8909e42b03af780a15/build_and_push.sh#L27-L29