Crate Validation Automated Tests

[douglowe]

Set up:

• Integration tests
• Unit tests
• Automation of the tests using Github actions

[douglowe]

RO-Crate metadata API PR includes metadata API tests, and integration tests: #56
MinIO Utils tests: #59
Validation Tasks tests: #60
Validation Services tests: #61

[douglowe]

To do:

• Integration tests require external web access, can this be disabled / add a random wait to the workflow to avoid getting blocked

[douglowe]

Closed as a duplicate of issue: #58