fix spider-gazelle not launching enough workers (#4191)

* fix spider-gazelle not launching enough workers

* spider-gazelle remove copy of spec folder

frameworks/Crystal/spider-gazelle/spider-gazelle.dockerfile

@@ -1,14 +1,15 @@
 FROM crystallang/crystal:0.27.0
-ADD . /src
-WORKDIR /src
+WORKDIR /usr/src/app
+
+COPY shard.yml ./
+COPY src src
 
 # Build App
-RUN shards build --production
+RUN shards build --release --no-debug
 
 ENV DATABASE_URL postgres://benchmarkdbuser:benchmarkdbpass@tfb-database:5432/hello_world?initial_pool_size=8&max_pool_size=8&max_idle_pool_size=8
 ENV SG_ENV production
 
 # Run the app binding on port 8080
 EXPOSE 8080
-ENTRYPOINT ["/src/bin/app"]
-CMD ["/src/bin/app", "-b", "0.0.0.0", "-p", "8080", "-w", "0"]
+CMD bin/app -w $(nproc) -b 0.0.0.0 -p 8080