add e2e smoke testing (UI) [initial version]

[schmidt-scaled]

login
access existing organization
access existing branch
resize branch up
--> validate that project limits are observed (rulers limited to remaining project limit)
--> validate that new limits have been applied to branch
resize branch down again
--> validate that new limits have been applied to branch
create new organization
create project, try maximum sizing
--> validate against org limits
create branch, try maximum sizing
--> validate against project limits
adjust sizing to 4 vcpu, 8GB, 200GB, 10000 IOPS
---> validate that branch is created
----> measure time
----> check that branch is active and healthy and correctly sized
delete branch
delete project
delete organization
---> all gone

Once this is working, we will create another backlog item to expand it