fix(healthcheck): Add a 2 second timeout to the healthchecks

[iainsproat]

Description & motivation

Addresses issue identified in #1649 (comment)
We cause the request itself to timeout if no response within 2 seconds, rather than relying on the healthcheck to timeout (this seemed to return a -1 or 127 status code). Relying on the healthcheck timeout seemed to cause docker to retry the healthcheck rather than restart the container.

If the healthcheck fails for any reason, the exit code must be 1 as this is the only exit code that docker identifies as 'unhealthy'.

Changes:

To-do before merge:

Screenshots:

Validation of changes:

Checklist:

• My pull request follows the guidelines in the Contributing guide?
• My pull request does not duplicate any other open Pull Requests for the same update/change?
• My commits are related to the pull request and do not amend unrelated code or documentation.
• My code follows a similar style to existing code.
• I have added appropriate tests.
• I have updated or added relevant documentation.

References