Add auto-cleaning of the shared cargo cache.

.lighthouse/pipeline-rust-test.yaml

@@ -164,6 +164,21 @@ spec:
             value: failure
           - name: TARGET_URL
             value: "https://tekton.fizz.buzz/#/namespaces/$(context.pipelineRun.namespace)/pipelineruns/$(context.pipelineRun.name)"
+      - name: cargo-cache-autoclean
+        taskRef:
+          name: run-docker-image
+        workspaces:
+          - name: source
+            workspace: git-source
+          - name: cargo-cache
+            workspace: cargo-cache
+        params:
+          - name: command
+            value: [cargo, cache, --autoclean]
+          - name: args
+            value: []
+          - name: docker-image
+            value: "$(params.image-name):$(tasks.fetch-repository.results.commit)"
     workspaces:
       - name: git-source
       - name: docker-credentials

docker/organic_test/Dockerfile

@@ -1,3 +1,4 @@
 FROM rustlang/rust:nightly-alpine3.17
 
 RUN apk add --no-cache musl-dev emacs
+RUN cargo install --locked cargo-cache