Description

Let's add some validation rule to the new traffic limit exception UI as a way to avoid human mistakes and improve the user experience

Acceptance criteria

• A traffic limit exception cannot be removed when still active
• There are no more than one traffic limit exception for the same experiment
• The traffic field is an integer value between 1 and 100
• The category field can be only one of the following values: editing, account-creation or other
• When editing is selected as value for category field, the traffic one will be automatically filled by default with 25%
• When account-creation is selected as value for category field, the traffic one will be automatically filled by default with 50%

Nice to have

• The experiment name field is an auto-complete dropdown list where the user can choose any existing experiment from GrowthBook (we could use the GrowthBook API to get that information)
• The experiment machine-readable name is automatically filled when an experiment name is chosen according to the above (we could use the GrowthBook API to get that information)