Add better parsing for the entrypoint

This would cause some variables not to parse correctly when running the entrypoint.

java/entrypoint.sh

@@ -40,7 +40,7 @@ java -version
 # Convert all of the "{{VARIABLE}}" parts of the command into the expected shell
 # variable format of "${VARIABLE}" before evaluating the string and automatically
 # replacing the values.
-PARSED=$(echo "$STARTUP" | sed -e 's/{{/${/g' -e 's/}}/}/g')
+PARSED=$(echo "${STARTUP}" | sed -e 's/{{/${/g' -e 's/}}/}/g' | eval echo "$(cat -)")
 
 # Display the command we're running in the output, and then execute it with eval
 printf "\033[1m\033[33mslice@pizzabyte~ \033[0m"