Written Dirac scheduler / filesystem

[sverhoeven]

Refs #38

TODO

1. [x] job submission
2. [x] job input from local to grid storage
3. [x] job input from grid storage to compute site
4. [x] job output from compute site to grid storage
5. [x] job output from grid storage to local
6. [x] dirac test suite
7. [x] dirac test suite in CI
8. [x] dev container
9. [x] clean up commented out code
10. [x] fix TODOs in code or convert to issues
11. [x] make logging less verbose
12. [x] get CI green
13. [x] make bartender work without DIRAC installed
14. [x] move tests for dirac /tests-dirac/test*.py inside /tests and use pytest markers to run non-dirac tests by default and dirac tests when specified.
15. [x] Handle when proxy has expired, in test container valid for 24 hours.

This PR adds the bartender.filesystems.dirac.DiracFileSystem and bartender.schedulers.dirac.DiracScheduler classes. To test them you

• can run their tests
• can play around with DIRAC using a dev container
• can spinup a bartender webservice with DIRAC and submit a job

[sverhoeven]

Thanks for reviewing.

There are 2 types of auth in bartender.

1. To consume the web service you need auth
2. Some destinations need auth, like dirac or slurm over ssh. A job submitted via the web services requires auth, but job is run by destination user/proxy on destination machine.