ci: Use gotestfmt to format go test output

The output of go test is notoriously hard to read, especially when a lot
of tests are executed and a lot of output is produced, which is the case
in our CI.

This commit uses gotestfmt to format the go test output. It only prints
the output of failed tests to stdout, because that's what we're usually
interested in. In case we need the full test output, that's now uploaded
as an artifact.

.github/workflows/ci.yml

@@ -28,6 +28,16 @@ jobs:
         with:
           go-version-file: go.mod
 
+      - name: Prepare tests artifacts path
+        run: |
+          set -eu
+
+          artifacts_dir=$(mktemp -d --tmpdir authd-test-artifacts-XXXXXX)
+          echo AUTHD_TEST_ARTIFACTS_DIR="${artifacts_dir}" >> $GITHUB_ENV
+
+      - name: Install gotestfmt and our wrapper script
+        uses: canonical/desktop-engineering/gh-actions/go/gotestfmt@gotestfmt
+
       - name: Run tests (with coverage collection)
         run: |
           set -eu
@@ -37,22 +47,24 @@ jobs:
           rm -fr "${raw_cov_dir}"
           mkdir -p "${raw_cov_dir}"
 
+          # Print executed commands to ease debugging
+          set -x
+
           # Overriding the default coverage directory is not an exported flag of go test (yet), so
           # we need to override it using the test.gocoverdir flag instead.
           #TODO: Update when https://go-review.googlesource.com/c/go/+/456595 is merged.
-          go test -cover -covermode=set ./... -shuffle=on -args -test.gocoverdir="${raw_cov_dir}"
+          go test -json -cover -covermode=set ./... -shuffle=on -args -test.gocoverdir="${raw_cov_dir}" 2>&1 | \
+            gotestfmt --logfile "${AUTHD_TEST_ARTIFACTS_DIR}/gotestfmt.cover.log"
 
           # Convert the raw coverage data into textfmt so we can merge the Rust one into it
           go tool covdata textfmt -i="${raw_cov_dir}" -o="/tmp/coverage.out"
 
           # Filter out the testutils package and the pb.go file
           grep -v -e "testutils" "/tmp/coverage.out" >"/tmp/coverage.out.filtered"
 
-      - name: Run tests (with race detector)
-        run: |
-          go test -race ./...
-
-      - name: Upload coverage to Codecov
-        uses: codecov/codecov-action@v4
+      - name: Upload test artifacts
+        if: failure()
+        uses: actions/upload-artifact@v4
         with:
-          file: /tmp/coverage.out.filtered
+          name: authd-${{ github.job }}-artifacts-${{ github.run_attempt }}
+          path: ${{ env.AUTHD_TEST_ARTIFACTS_DIR }}