MR refactor: Disable toggle comments button when diff has no discussions
MR refactor: Disable/Remove toggle comments button when diff has no discussions.
Currently, when the user clicks the toggle comment button and the diff has no discussions, nothing happens.
We should at least disable it to avoid unnecessary calls to the store ~performance
@tauriedavis would it be better to remove it?
/cc @andr3 @timzallmann