test: use void to indicate "useless" expressions
Instead of disabling the no-unused-expressions ESLint rule, mark
intentional "useless" expressions with void.
Refs: https://eslint.org/docs/rules/no-unused-expressions#options
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Instead of disabling the no-unused-expressions ESLint rule, mark
intentional "useless" expressions with void.
Refs: https://eslint.org/docs/rules/no-unused-expressions#options