Revert NodeJS version to 14

[felddy]

🗣 Description

Revert NodeJS version from 16 to 14.

This closes issue #196

💭 Motivation and Context

As usual, I've been a bit more aggressive with versions.

Related issues:

• Core dump on node:16-alpine3.13 (arm) nodejs/docker-node#1477
• Seccomp blocks install of "libc6" in Ubuntu 20.04 "focal" image on armhf (arm32v7) moby/moby#40734
• alpine 3.13, armv7 network-access seems to be broken alpinelinux/docker-alpine#135

🧪 Testing

• Locally
• CI
• Hopefully @vehrka will be able to test.

📷 Screenshots (if appropriate)

✅ Checklist

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

[felddy]

@vehrka could you try testing with this image: felddy/foundryvtt:bugfix-node14

This is going to be version 0.8.5 of FoundryVTT.

[vehrka]

@vehrka could you try testing with this image: felddy/foundryvtt:bugfix-node14

This is going to be version 0.8.5 of FoundryVTT.

I can confirm that with felddy/foundryvtt:bugfix-node14 I have Foundry 0.8.5 up and running in my raspi!!!!

[felddy]

I can confirm that with felddy/foundryvtt:bugfix-node14 I have Foundry 0.8.5 up and running in my raspi!!!!

@vehrka I've released a new build on the :beta tag. It should be done in a few minutes:
https://github.com/felddy/foundryvtt-docker/actions/runs/882867160

You can then switch back to using that tag :beta and pull the new image.

Thank you again for your help.