🗣 Description

The container will alway try to see if a newer (by timestamp) distribution for the current version of FoundryVTT exists. This is because newer distributions have been published in the past without bumping the version of FoundryVTT.

This PR will allow the container to fail back to the cache when there is a network failure while trying to fetch the latest release of FoundryVTT, or check the timestamp in the r2 bucket.

Some cases where this can happen are:

• the FOUNDRY_RELEASE_URL is set to an expired timed URL.
• the FOUNDRY_USERNAME or FOUNDRY_PASSWORD are invalid.
• foundryvtt.com is down.
• r2.foundryvtt.com is down.

Closes #212
Closes #1055

See:

• Allow starting of container if foundryvtt.com is down, and release zip has already been downloaded #212
• Unraid; Will only build from Timed URL #1055

💭 Motivation and context

It was annoying that a network failure didn't result in automatically failing back to the cache. Users had to
manually disable their credentials, or remove the timed URL.

🧪 Testing

Tested locally and in CI.

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• All future TODOs are captured in issues, which are referenced
  in code comments.
• All relevant type-of-change labels have been added.
• I have read the CONTRIBUTING document.
• These code changes follow cisagov code standards.
• All relevant repo and/or project documentation has been updated
  to reflect the changes in this PR.
• Tests have been added and/or modified to cover the changes in this PR.
• All new and existing tests pass.