update readme urls and docker file go 1.81 -> 1.21

[tjex]

As stated in title.

In preparation for zk release 0.14.1

[tjex]

hmm. I see a problem here, that this would require a zk-org account on docker hub. Closing for now.

[mcDevnagh]

why don't we make a zk-org account?

[tjex]

Since writing this, I'm unsure if a shared account makes so much sense. 1. We can build locally from the images in this repo 2. I think it's worth looking at transitioning away from mattn's sqlite library, so we don't need to cross compile with Docker in the first place. That being said, if you and or others still consider a shared account to be the best way, then I'm down. It would be great then if someone could then make it. Not sure how to share the password. Maybe someone has 1password and can share an encrypted one time sharing of the password that we can insert into our own managers.

[julio-lopez]

Why not push to Github (ghcr) instead of Docker (Hub) ? That is simpler and does not require creating a separate account / org with Docker and maintaining credentials, etc.

[tjex]

Ah awesome. Didn't know this was a thing. Sounds like the best solution. I'll set this up once the `musl` images are done zk-org/zk#411 And will then update / close #4, whichever makes most sense given the `ghcr` setup.