ci: change cargo chef call so it will ignore the GUI client (#3740)

I don't know much about `cargo chef` so I gave this its own PR in case
I'm doing something that'll subtly break it
I've run into this problem on some branches and not others, where it's
trying to build all the Tauri / glib stuff even though the Docker image
won't need it:
https://github.com/firezone/firezone/actions/runs/8012206575/job/21887478015#step:7:1175

rust/Dockerfile

@@ -12,7 +12,7 @@ FROM alpine:${ALPINE_VERSION} as rust
 # is updated with the current date. It will force refresh of all
 # of the base images and things like `apk add` won't be using
 # old cached versions when the Dockerfile is built.
-ENV REFRESHED_AT=2023-12-11 \
+ENV REFRESHED_AT=2024-02-22 \
   LANG=C.UTF-8 \
   TERM=xterm
 
@@ -68,7 +68,7 @@ RUN set -xe \
 WORKDIR /build
 
 # Create a cache recipe for dependencies, which allows
-# to levearge Docker layer caching in a later build stage
+# to leverage Docker layer caching in a later build stage
 FROM chef as planner
 
 COPY . .
@@ -80,8 +80,9 @@ FROM chef as builder
 
 COPY --from=planner /build/recipe.json .
 
+ARG PACKAGE
 RUN set -xe \
-  && cargo chef cook --recipe-path recipe.json
+  && cargo chef cook --recipe-path recipe.json --bin ${PACKAGE}
 
 COPY . .