Add alias for `cargo_bootstrap_repository` binaries (#1160)

diff --git a/cargo/cargo_bootstrap.bzl b/cargo/cargo_bootstrap.bzl
index 6d6cdcf..bbe35c0 100644
--- a/cargo/cargo_bootstrap.bzl
+++ b/cargo/cargo_bootstrap.bzl
@@ -116,6 +116,11 @@
     "{binary}"
 ])
 
+alias(
+    name = "binary",
+    actual = "{binary}",
+)
+
 rust_binary(
     name = "install",
     rustc_env = {{