post https://a.klaviyo.com/api/tag-groups/
Create a tag group. An account cannot have more than 50 unique tag groups.
If exclusive is not specified true or false, the tag group defaults to non-exclusive.
If a tag group is non-exclusive, any given related resource (campaign, flow, etc.)
can be linked to multiple tags from that tag group.
If a tag group is exclusive, any given related resource can only be linked to one tag from that tag group.
Rate limits:
Burst: 3/s
Steady: 60/m
Scopes:
tags:read
tags:write