Update build_dev_container.sh (#2189)

Author: seanpmorgan

tools/build_dev_container.sh

@@ -4,7 +4,7 @@ set -x -e
 
 DOCKER_BUILDKIT=1 docker build \
     -f tools/docker/dev_container.Dockerfile \
-    --build-arg TF_VERSION=2.2.0 \
+    --build-arg TF_VERSION=2.3.0 \
     --build-arg TF_PACKAGE=tensorflow-cpu \
     --target dev_container_cpu \
     -t tfaddons/dev_container:latest-cpu ./