chore: remove rclone (#1447)

since unraid will ship with it natively, starting at 7.2.

rclone support is not planned for earlier releases.
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Chores**
* Removed an unnecessary step from the build process, streamlining
operations.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

plugin/builder/build-txz.ts

@@ -10,7 +10,6 @@ import { cleanupTxzFiles } from "./utils/cleanup";
 import { apiDir } from "./utils/paths";
 import { getVendorBundleName, getVendorFullPath } from "./build-vendor-store";
 import { getAssetUrl } from "./utils/bucket-urls";
-import { ensureRclone } from "./utils/rclone-helper";
 
 
 // Recursively search for manifest files
@@ -176,7 +175,6 @@ const buildTxz = async (validatedEnv: TxzEnv) => {
   
   await Promise.all([
     ensureNodeJs(),
-    ensureRclone()
   ]);
 
   // Create package - must be run from within the pre-pack directory