third_party/nix: make run launch-multi2 work

This makes commands like `bazel run //:launch-multi2` work in the
nix-shell which is nicer than running it inside a Bazel test.

Long-term we should work on reducing these ambient deps, but
considering all the other deps in that list I think this makes sense for
the time being.

Change-Id: Iaef701f19bf363536e415b9a0c51a220b8785ca6
Reviewed-on: https://review.monogon.dev/c/monogon/+/2337
Tested-by: Jenkins CI
Reviewed-by: Tim Windelschmidt <tim@monogon.tech>
diff --git a/third_party/nix/env.nix b/third_party/nix/env.nix
index 473e0fd..c293036 100644
--- a/third_party/nix/env.nix
+++ b/third_party/nix/env.nix
@@ -87,6 +87,8 @@
     busybox
     niv
     google-cloud-sdk
+    qemu_kvm
+    swtpm
   ];
   runScript = wrapper;
 })