Add Agda Tests

[rzuckerm]

Congrats on taking the first step to contributing to the Sample Programs repository maintained by The Renegade Coder!
For simplicity, please make sure that your pull request includes one and only one contribution.

Please fill one of the sections below as applicable.
Please also add any other relevant information to the Notes section at the bottom.
You may delete or just ignore any other sections.
For more information please refer to our contributing documentation

I Am Adding New Tests for a Language

• I fixed Add Agda Testing #3516
• I named the pull request using Add {LANGUAGE} Tests format
• I added a testinfo.yml files (see contributing documentation)
  • I used an officially supported docker image or one that I personally trust
• I verified all tests are passing

Other Notes

I had to modify the "hello world" sample to get it to work.

[jrg94]

Wow! Very strange looking language that requires many imports.