update cache handler version in example (#65330)
### What?
Update the cache-handler package to the latest and changed logic for
opting out of caching during build.
### Why?
The current implementation in the cache-handler-redis example requires
an environment variable check for `REDIS_AVAILABLE` to determine if the
server has already started in order to opt out of caching during build.
This update leverages the `NEXT_PHASE` environment variable instead.
### How?
This updates the environment variable check to leverage the `NEXT_PHASE`
variable so a user doesn't have to manage a new environment variable.
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Co-authored-by: JJ Kasper <jj@jjsweb.site>
