update justfile to build containers launcher with bazel

since the oak containers launcher is bazelified, we can start
using bazel to build it. also, this change would allow the launcher
to work on a old version of debian with old glibc.

Change-Id: I38c379c1f2e9871a140311698a56a8f032fdcde2

justfile

@@ -224,7 +224,9 @@ oak_containers_kernel:
         $(realpath oak_containers)/kernel/bin/subjects
 
 oak_containers_launcher:
-    cargo build --release --package=oak_containers_launcher
+    bazel build {{BAZEL_CONFIG_FLAG}} //oak_containers/launcher:oak_containers_launcher
+    cp bazel-bin/oak_containers/launcher/oak_containers_launcher \
+        $(realpath artifacts/oak_containers_launcher)
 
 # Profile the Wasm execution and generate a flamegraph.
 profile_wasm: