Example when called from vscode (and everything is hooked up):
```
> * User-Agent: bricks/0.0.21-devel databricks-sdk-go/0.2.0 go/1.19.4 os/darwin upstream/databricks-vscode
```
This configures the user agent with the bricks version and the name of
the command being executed.
Example user agent value:
```
> * User-Agent: bricks/0.0.21-devel databricks-sdk-go/0.2.0 go/1.19.4 os/darwin cmd/sync auth/pat
```
This is a follow up for #194.
Not settled whether this should live as a top level command or hidden
under some debug scope. Either way, the ability to make arbitrary API
calls and leverage unified auth is a super useful tool.