Retry fork tests in CI.

[jubeira]

Description

Retry a few times if the tests fail in CI, with a delay in between each attempt. Hopefully should improve CI success rates, which are pretty bad lately.

Type of change

• Bug fix
• New feature
• Breaking change
• Dependency changes
• Code refactor / cleanup
• Documentation or wording changes
• Other

Checklist:

• The diff is legible and has no extraneous changes
• Complex code has been commented, including external interfaces
• N/A Tests are included for all code paths
• The base branch is either master, or there's a description of how to merge

Issue Resolution

N/A

[jubeira]

This kinda works, but if the test fails in the before hook there's not much we can do.

See mochajs/mocha#4006 and mochajs/mocha#4658.