Add tests

[Divide-By-0]

For the regex generation flow, add a few sample regexes or regex configs, then generate a final circom file and use circom-tester to ensure that it in fact correctly matches that regex and reveals the right group. This will be needed to merge in #31.

[SoraSuegami]

The generated circuits are already tested here.
https://github.com/zkemail/zk-regex/tree/main/packages/circom/tests
Those tests automatically generate the circom circuits for the regexes in the circom package and check the revealed substrings.