Fix Dockerfile on arm64

[Whizanth]

Now that the issue with zippy has been fixed (#756), the only thing preventing Nitter's Dockerfile to successfully build on arm64 is the Nim image.

To solve this, we can use the regular Alpine image, and install Nim manually.

With the changes in this pull request, I was successfully able to build the Nitter image on both arm64 and x86_64.

[unixfox]

No nim version is enforced in this Dockerfile, I would suggest deploying as a separate Docker image like for invidious: https://github.com/iv-org/invidious/blob/master/docker/Dockerfile.arm64

[Whizanth]

I've updated my fork to use a separate Dockerfile for arm64, as you suggested.

As for enforcing the Nim version, as far as I'm able to tell, the latest Nim version that's available in the Alpine repositories is 1.6.8-r0. In contrast, the official Dockerfile for x86 uses 1.6.10, which is newer, so I don't think enforcing an older version would be a good idea, tell me if you don't agree.

If all of this is okay, do I need to squash my commits into one before you merge?

[unixfox]

As for enforcing the Nim version, as far as I'm able to tell, the latest Nim version that's available in the Alpine repositories is 1.6.8-r0. In contrast, the official Dockerfile for x86 uses 1.6.10, which is newer, so I don't think enforcing an older version would be a good idea, tell me if you don't agree.

That doesn't really matter, it's to avoid using a newer version if one day alpine edge have a much newer version than the version specified in the official Dockerfile.

[zedeus]

Thanks, this looks good. Assuming Docker can automatically use this file to build an ARM image, this should also be reverted: 2aa07e7

[unixfox]

Thanks, this looks good. Assuming Docker can automatically use this file to build an ARM image, this should also be reverted: 2aa07e7

Here it's a different Dockerfile, it can't be built with the original Dockerfile image.

I think @Whizanth you will need to add a github workflow for pushing the image too.

[unixfox]

Please see my comments

[zedeus]

Thank you!

[Whizanth]

You're welcome! The GitHub workflow will still have to be added though, but I'm not familiar with it.