6.4.0-beta.1

Various fixes & improvements

• Fix: Disable log by default in debug mode (#753)
• [Dio] Ref: Replace FailedRequestAdapter with FailedRequestInterceptor (#728)
• Fix: Add missing return values - dart analyzer (#742)
• Feat: Add DioEventProcessor which improves DioError crash reports (#718)
• Fix: Do not report duplicated packages and integrations (#760)