Update Dockerfile

Signed-off-by: jinwei.fan <jinwei.fan@samsung.com>
Change-Id: I23a7ef0ef2e5c3bb810ff85cab36ff892451c799
diff --git a/Dockerfile b/Dockerfile
index 562e17a..4652071 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM nexus3.o-ran-sc.org:10004/o-ran-sc/bldr-ubuntu18-c-go:8-u18.04 as kpimonbuild
+FROM nexus3.o-ran-sc.org:10004/o-ran-sc/bldr-ubuntu18-c-go:1.9.0 as kpimonbuild
 
 ENV PATH $PATH:/usr/local/bin
 ENV GOPATH /go