Don't verify during download via curl (#862)

Motivation:

Our curl version is too old, just don't verify while download sdkman

Modifications:

Download via -k

Result:

Build docker image again

docker/Dockerfile.debian

@@ -52,11 +52,11 @@ RUN wget -q --no-check-certificate https://github.com/netty/netty-tcnative/relea
 
 RUN rm -rf $SOURCE_DIR
 
+
 # Downloading and installing SDKMAN!
+RUN echo '-k' > $HOME/.curlrc
 RUN curl -s "https://get.sdkman.io" | bash
-
-ARG java_version="8.0.302-zulu"
-ENV JAVA_VERSION $java_version
+RUN rm $HOME/.curlrc
 
 # Don't check the certificates as our curl version is too old.
 RUN echo 'sdkman_insecure_ssl=true' >> $HOME/.sdkman/etc/config
@@ -67,6 +67,9 @@ RUN bash -c "source $HOME/.sdkman/bin/sdkman-init.sh && \
     rm -rf $HOME/.sdkman/archives/* && \
     rm -rf $HOME/.sdkman/tmp/*"
 
+ARG java_version="8.0.302-zulu"
+ENV JAVA_VERSION $java_version
+
 RUN echo 'export JAVA_HOME="/root/.sdkman/candidates/java/current"' >> ~/.bashrc
 RUN echo 'PATH=$JAVA_HOME/bin:$PATH' >> ~/.bashrc