Add registry probing to integration test suite

[michael-valdron]

Please specify the area for this PR

integration tests

What does does this PR do / why we need it:

Add the optional ability to enforce a successful health check probe on the target registry in order to run tests. This feature is required to fix staging deployment problems due to the acceptance testing running before the deployment is ready.

Additional Changes

• Registry viewer test case has been revised to work with the new registry viewer content
• Error handling has been added for the getting and setting of environment variables

Which issue(s) this PR fixes:

Fixes #?

fixes devfile/api#1086

PR acceptance criteria:

• Test Coverage
  • Are your changes sufficiently tested, and are any applicable test cases added or updated to cover your changes?

Documentation (WIP)

• Does the REST API doc need to be updated with your changes?
• Does the registry library doc need to be updated with your changes?

How to test changes / Special notes to the reviewer:

1. Build the container image

   bash docker-build.sh

2. Run the container against a deploying target registry with the PROBE_TIMEOUT environment variable set

   docker run --rm --env REGISTRY=$REGISTRY --env PROBE_TIMEOUT=60 devfile-registry-integration

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (0f64fa1) 42.69% compared to head (a7e9a4e) 42.69%.

❗ Current head a7e9a4e differs from pull request most recent head bab6ff6. Consider uploading reports for the commit bab6ff6 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #170   +/-   ##
=======================================
  Coverage   42.69%   42.69%           
=======================================
  Files           6        6           
  Lines        1047     1047           
=======================================
  Hits          447      447           
  Misses        557      557           
  Partials       43       43           

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: kim-tsao, michael-valdron
Once this PR has been reviewed and has the lgtm label, please assign maysunfaisal for approval. For more information see the Kubernetes Code Review Process.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment