params
Set request query/form parameters for the most recently added webhook. Writes
to the params key of the webhook definition.
params() is not an alias for body(). They write to different keys in the
webhook specification: body sets the request body, while params sets
query/form parameters.
Parameters
data
Request parameters. Supports ${variable} substitutions.
Returns
DataMap — Self for method chaining. Throws an Error if no webhook
has been added yet.