Optimize CI run time

By doing a single `cargo build` ahead of time, we are creating all
necessary binaries at once. This allows our cache to work for tests
as well as the binaries.

There is also no need to use release binaries for the smoke test.
Building debug binaries is a lot faster and serves the same purpose:
Checking whether the application actually starts up.

.github/workflows/ci.yml

@@ -62,12 +62,12 @@ jobs:
           override: true
           toolchain: stable
       - uses: Swatinem/rust-cache@v1.3.0
-      - run: cargo test --workspace --all-features
-      - run: cargo build --target=${{ matrix.target }} --release --bin maker --bin taker
-      - name: Smoke test ${{ matrix.target }} release binary
+      - run: cargo build --all-targets --all-features
+      - run: cargo test --workspace
+      - name: Smoke test ${{ matrix.target }} binary
         run: |
-          target/${{ matrix.target }}/release/maker &
+          target/debug/maker &
           sleep 5s # Wait for maker to start
-          target/${{ matrix.target }}/release/taker &
+          target/debug/taker &
           sleep 5s # Wait for taker to start
           curl --fail http://localhost:8000/alive