chore: update references and links to the repo

[meszarosdezso]

The repo was recently renamed from deno_website2 to dotland, this updates some references across the files.

I've updated:

• the title and the CI badge in the readme
• the CI badge in the footer
• all the references to issues in the repo (the old links still work, but I think it's nicer to have the correct git url)
• the links to submit new artwork and translations

I've not touched:

• the project name in the package.json (I am not sure that would break anything?)
• the links to translations, as they're on forks

[kt3k]

@meszarosdezso LGTM. Thank you!