THRIFT-3907 Skip Docker image build on CI when unchanged
diff --git a/build/docker/debian/Dockerfile b/build/docker/debian/Dockerfile
index 285c85b..99eda7a 100644
--- a/build/docker/debian/Dockerfile
+++ b/build/docker/debian/Dockerfile
@@ -186,5 +186,5 @@
 
 ENV THRIFT_ROOT /thrift
 RUN mkdir -p $THRIFT_ROOT/src
-COPY scripts $THRIFT_ROOT
+COPY Dockerfile $THRIFT_ROOT/
 WORKDIR $THRIFT_ROOT/src