Avoid Bundler deprecation warning by using 'bundle config set path'

From Bundler's output:

> Using the config command without a subcommand [list, get, set, unset] is deprecated and will be removed in the future.

Author: duckinator

crates/rb-core/src/bundler/mod.rs

@@ -244,7 +244,7 @@ impl BundlerRuntime {
         );
 
         let status = Command::new("bundle")
-            .args(["config", "path", "--local"])
+            .args(["config", "set", "path", "--local"])
             .arg(self.vendor_dir().to_string_lossy().as_ref())
             .current_dir(&self.root)
             .status_with_context(butler_runtime);