Originally ACs for {T396059}, we decided to spin this feature into its own ticket given the product and analytics impacts of allowing for changes in traffic during an active experiment.
==Description
Add new validation rules to xLab experiments form:
[] Allow for additional wikis and increase of sample rate for activated experiments – [[ https://www.figma.com/design/Tcc2kiPAcsXVK2t6qC1QrV/Experiment-Platform---XLab?node-id=4715-138146&t=UE5plbwBwDy7Usv4-0 | Initial design specs ]]
[] Prohibit destructive changes to traffic while experiment is active (i.e. no decrease of sample rates and no removal of wikis)
[] Determine if same rules apply to instruments
==Acceptance Criteria
[] Above validation rules are implemented
[] Unit tests are added to capture validation errors
[] Relevant documentation is updated