docs: change rule desc input to textarea in new-rule template

Author: aladdin-add

.github/ISSUE_TEMPLATE/new-rule.yml

@@ -8,7 +8,7 @@ body:
 - type: markdown
   attributes:
     value: By opening an issue, you agree to abide by the [Open JS Foundation Code of Conduct](https://eslint.org/conduct).
-- type: input
+- type: textarea
   attributes:
     label: Rule details
     description: What should the new rule do?