WHAT
Review the work already done for Redis Creation. 

Implement any missing logic for updating an existing Redis instance using an update strategy - this should also include adding tags/labels to the instances, similar to how it's done in AWS.

HOW
See this block in AWS that performs the update when the instance exists using the update strategy.

It may be possible to update the version number along with the other instance metadata using UpdateInstance, however if this does not trigger a version update, an extra check will need to take place on the instance version in the strategy and use the UpgradeInstance function instead.

TESTS
Add required unit tests.

DONE
A Redis instance can be modified via the update strategy.