use gradle v4.10 in test docker container

Author: holgerbrandl

misc/Dockerfile

@@ -16,5 +16,9 @@ ENV JAVA_HOME /usr/lib/jvm/java-8-openjdk-amd64/
 # install sdkman (see http://sdkman.io/install.html)
 RUN bash -c "curl -s 'https://get.sdkman.io' | bash"
 
+# install assert.h
+RUN bash -c "cd /bin && wget https://raw.githubusercontent.com/lehmannro/assert.sh/master/assert.sh && chmod u+x assert.sh"
+
+
 #tall kotlin and maven
-RUN /bin/bash -c 'source ~/.sdkman/bin/sdkman-init.sh && sdkman_auto_answer=true && sdk install kotlin && sdk install maven && sdk install gradle'
+RUN /bin/bash -c 'source ~/.sdkman/bin/sdkman-init.sh && sdkman_auto_answer=true && sdk install kotlin && sdk install maven && sdk install gradle 4.10'