The reference to `docker.Copy` does not exist and should be `docker.#Copy` instead. This also leads to a confusing error message (possibly related to #493) as it isn't found while CUE is compiled, and instead results in the following runtime error:
```
[✗] actions.deps 2.1s
9:16PM FTL failed to execute plan: task failed: actions.deps._dag."2"._exec: invalid FS at path "actions.deps._dag.\"2\"._exec.input": FS is not set
```
Signed-off-by: Ben Gesoff <ben@gesoff.uk>
So that we get auto-formatting and syntax checking in our code editor.
The only snippets which have not been extracted are either terminal
output, or file fragments (e.g. CUE) which are not valid standalone files.
Resolves https://github.com/dagger/dagger/issues/1715
While at it, do a few fly-by improvements:
- beta.1 -> beta.2
- add CUE & BuildKit links
- up -> do
Signed-off-by: Gerhard Lazu <gerhard@lazu.co.uk>