Rebuild of the github action to work with the new w3up web3.storage api.

[`w3cli`](https://github.com/web3-storage/w3cli) does everything we need to upload files to web3.storage, so this action now provides a thin wrapper around that cli in the form of a composite action.

Auth is based on UCANs now. Use w3cli to create a signing key for this action to use, and create a ucan that delegates upload abilities to that key.

- input: `web3_token` has been removed, as token based auth as been removed.
  - set `secret_key` to a base64 encoded siging key you create via `w3 key create`.
  - set `proof` to the a base64 CAR encoded UCAN delegating capabilities to the secret_key's DID.
- input: `wrap_with_directory` has been removed. w3cli does not wrap directories in directories by default now. Only single files get wrapped to preserve their filename.
  - set `no_wrap: 'true'` to disable the wrapping of single files.
- input: `web3_api` has been removed. Targeting other services is not currently supported. Open an issue if you need that.

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

Co-authored-by: Alan Shaw <alan.shaw@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>

License: MIT
Signed-off-by: Oli Evans <oli@protocol.ai>