Reduce compose build disk footprint further

.github/workflows/lint.yml

@@ -198,6 +198,10 @@ jobs:
       - name: Prepare workspace tmpdir
         run: mkdir -p "$TMPDIR"
 
+      - name: Prune docker to free space
+        run: |
+          docker system prune -af --volumes || true
+
       - name: Install Rust toolchain
         uses: dtolnay/rust-toolchain@master
         with:

testing-framework/assets/stack/Dockerfile

@@ -76,6 +76,8 @@ RUN mkdir -p /opt/circuits && \
 ENV NOMOS_CIRCUITS=/opt/circuits
 ENV CARGO_TARGET_DIR=/tmp/target
 ENV CARGO_INCREMENTAL=0
+ENV CARGO_PROFILE_DEV_DEBUG=0
+ENV RUSTFLAGS="-C debuginfo=0"
 
 # Fetch the nomos-node sources pinned in Cargo.lock and build the runtime binaries.
 RUN if [ ! -d /workspace/nomos-node ]; then \