MB-51565 Don't validate --purge-interval value
MB-51565 Don't validate --purge-interval value

We only did this in one place (bucket create) but it meant whenever
ns_server changes what values it allows here we'd have to update
couchbase-cli. The error message we get from the REST API is nice enough
that we can just show that instead

Change-Id: Iafae0c80afcc8529512325fe7d78a0a40cd0ba7c
Reviewed-on: https://review.couchbase.org/c/couchbase-cli/+/172847
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: James Lee <d8c596dede5f1eea3b1030b95e7922790d6e257e@couchbase.com>

couchbase/couchbase-cli,couchbase/couchbase-cli