Sentry's GitHub integration should allow filtering of existing issues by environment

### Problem Statement

Potentially a duplicate of https://github.com/getsentry/sentry/discussions/49996#discussioncomment-6807526. Sentry's GitHub integration adds existing issues to new PRs. It's a little overzealous about doing so though. If the Sentry project has a non-production "development" environment, it'll add issues from that environment when it probably shouldn't.

### Solution Brainstorm

The Sentry GitHub integration might allow a "environments" allowlist setting for posting related issues.

### Product Area

Settings - Integrations