7.21.0

• feat(react): Add tracing support for React Router 6.4 createBrowserRouter. (#6172)
• fix(core): Add guard against scope.getAttachments (#6258)
• fix(core): Only generate eventIds in client (#6247)
• fix(express): Support multiple routers with common paths. (#6253)
• fix(tracing): Pass tracePropagationTargets to instrumentOutgoingRequests (#6259)