get
Returns a map of fluid types - and their corresponding amounts - that can be supplied by the block for this fluid tick. deltaSeconds is the time since the last fluid tick.
If you have a machine that can supply up to 100 fluid per second, it should supply 100*deltaSeconds of that fluid
Any implementation of this method must NEVER call the same method for any other connection point, otherwise you risk creating infinite loops.
Called exactly one per fluid tick.