chore: remove unused variable
This removes a variable that wasn't being used (warnings were silenced because name was `_all`).
@@ -41,7 +41,6 @@ pub fn exec(env: &dyn Environment, opts: CanisterBuildOpts) -> DfxResult {
env.get_cache().install()?;
let build_mode_check = opts.check;
- let _all = opts.all;
// Option can be None in which case --all was specified
let canister_names = config
