chore(deps) Update Rust crate handlebars to v4 (#1904)

Co-authored-by: Renovate Bot <bot@renovateapp.com>

tooling/bundler/Cargo.toml

@@ -36,7 +36,7 @@ tar = "0.4"
 termcolor = "1.1.2"
 toml = "0.5.8"
 walkdir = "2"
-handlebars = { version = "3.5" }
+handlebars = { version = "4.0" }
 zip = { version = "0.5" }
 tempfile = "3.2.0"
 regex = "1"