Add Redis config entries in the Docker images to disable saving the database and to only provision 1 database.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

docker/Dockerfile

@@ -75,6 +75,12 @@ ln -s /usr/lib/arm-linux-gnueabihf/libjpeg.so /usr/lib/ \
 # Discard data when Redis runs out of memory
 RUN echo "maxmemory-policy allkeys-lru" >> /etc/redis/redis.conf
 
+# Disable saving the Redis database
+RUN echo "save \"\"" >> /etc/redis/redis.conf
+
+# Only provision 1 database
+RUN echo "databases 1" >> /etc/redis/redis.conf
+
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 # Build image start #
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