Setting within the Sentry UI to Globally Disable Performance Monitoring

### Problem Statement

Currently it is only possible to disable Performance Monitoring per project through the SDK config, see [related help article](https://sentry.zendesk.com/hc/en-us/articles/22720369975707-Can-I-globally-enable-or-disable-tracing). This is difficult to do for some users as they have dozens of projects which requires a lot of work when it comes to disabling/reenabling Performance Monitoring.

### Solution Brainstorm

Have a functionality within the Sentry UI Organization-wide settings that allows for global disabling/re-enabling of performance monitoring.

Related to internal ticket number [#165086](https://sentry.zendesk.com/agent/tickets/165086) see ticket for further context

### Product Area

Performance

The issue names no files, tests, or code entry points. Start by locating the organization-wide settings and performance-monitoring configuration, then clarify the behavior for disabling and re-enabling monitoring across all projects and define tests for the setting.

Written by the indexing model from the issue text.