[CI] Add check for shards binary in test_dist_linux_on_docker (#15394)

This is to detect issues like crystal-lang/distribution-scripts#330 directly in the build process.

.circleci/config.yml

@@ -477,6 +477,7 @@ jobs:
       - run: bin/ci prepare_system
       - run: echo 'export CURRENT_TAG="$CIRCLE_TAG"' >> $BASH_ENV
       - run: bin/ci prepare_build
+      - run: bin/ci with_build_env 'shards --version'
       - run:
           command: bin/ci build
           no_output_timeout: 30m