Split ENTRYPOINT to CMD in Dockerfile (#359)

diff --git a/Dockerfile b/Dockerfile
index df53ba2..ea7653e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -40,4 +40,5 @@
 COPY ./config/config.yaml /var/lib/kvctl/
 
 EXPOSE 9379:9379
-ENTRYPOINT ["./bin/kvctl-server", "-c", "/var/lib/kvctl/config.yaml"]
+ENTRYPOINT ["./bin/kvctl-server"]
+CMD ["-c", "/var/lib/kvctl/config.yaml"]