SBT version updated 1.4.5 -> 1.4.9 (#21)

Dockerfile

@@ -4,7 +4,7 @@
 ARG OPENJDK_TAG=8u232
 FROM openjdk:${OPENJDK_TAG}
 
-ARG SBT_VERSION=1.4.5
+ARG SBT_VERSION=1.4.9
 
 # Install sbt
 RUN \

README.md

@@ -42,7 +42,7 @@ Then use the following recipe to build and push:
 
 ```bash
 OPENJDK_TAG=8u232
-SBT_VERSION=1.4.5
+SBT_VERSION=1.4.9
 
 docker build \
     --build-arg OPENJDK_TAG=$OPENJDK_TAG \