Bulk Mutate a List of Issues API currently does not support unsubscribing from Issues

### Problem Statement When using the [Bulk Mutate a List of Issues API](https://docs.sentry.io/api/events/bulk-mutate-a-list-of-issues/), there is no option to configure subscribe/unsubscribe conditions. **Context:** Currently, the way Sentry works is that members of a team that are assigned an Issue are automatically subscribed to it If the team assignment subsequently changes, the team that was initially assigned will still be subscribed to those issues. **Ask:** As a user, I want to have the option to leverage the Bulk Mutate a List of Issues API to unsubscribe from Issues in the event where my ownership rules have assigned Issues to the wrong team. ### Solution Brainstorm _No response_ ### Product Area Issues ┆Issue is synchronized with this [Jira Improvement](https://getsentry.atlassian.net/browse/FEEDBACK-1883) by [Unito](https://www.unito.io)