build: tidy up the Ambient plan

Signed-off-by: Lars Wirzenius <liw@liw.fi>

.radicle/ambient.yaml

@@ -1,8 +1,14 @@
 pre_plan:
   - action: cargo_fetch
 plan:
-#  - action: cargo_fmt
-#  - action: cargo_clippy
+  - action: cargo_fmt
+  - action: cargo_clippy
+
+  # Not using the built-on `cargo_test` action, as the test suite
+  # requires HOME to be set and Ambient doesn't yet have a way to do
+  # that. So we use the `shell` action instead, even if that is more
+  # tedious and requires setting up the relevant environment variables
+  # manually.
   - action: shell
     shell: |
       export CARGO_TARGET_DIR=/workspace/cache
@@ -10,17 +16,9 @@ plan:
       export HOME=/root
       export PATH="/root/.cargo/bin:$PATH"
 
+      # Configure Git so that it can be used in the tests for this
+      # project.
       git config --global user.email "test@example.com"
       git config --global user.name "Testy McTestface"
 
-      env
-      ls -lA /root/.rustup/toolchains
-
-      command -v cargo
-      command -v rustc
-
-      rustup show
-      rustup toolchain list
-      rustc --version
       cargo test
-#  - action: cargo_test