fix(cli.rs/build): fix typo getting bundle arg (#1783)

.changes/fix-cli.rs-bundle-arg.md

@@ -0,0 +1,5 @@
+---
+"cli.rs": minor
+---
+
+Fix a typo that would result in bundle arg being ignored.

tooling/cli.rs/src/main.rs

@@ -119,7 +119,7 @@ fn build_command(matches: &ArgMatches) -> Result<()> {
   let target = matches.value_of("target");
   let debug = matches.is_present("debug");
   let verbose = matches.is_present("verbose");
-  let bundles = matches.values_of_lossy("bundles");
+  let bundles = matches.values_of_lossy("bundle");
   let config = matches.value_of("config");
 
   let mut build_runner = build::Build::new();