Update README with SonarQube badges

Added quality and reliability metrics from SonarQube to README.

Author: egelhaus

README.md

@@ -19,6 +19,10 @@
 </a>
 </p>
 
+<p align="center">
+[![Quality Gate Status](https://sonarqube.ennogelhaus.de/api/project_badges/measure?project=gitroomhq_postiz-app_bd4cd369-af44-4d19-903b-c4bdb0b66022&metric=alert_status&token=sqb_4ef7409d8d3bb84ff51d945f5a62bc0df93895a9)](https://sonarqube.ennogelhaus.de/dashboard?id=gitroomhq_postiz-app_bd4cd369-af44-4d19-903b-c4bdb0b66022) [![Maintainability Rating](https://sonarqube.ennogelhaus.de/api/project_badges/measure?project=gitroomhq_postiz-app_bd4cd369-af44-4d19-903b-c4bdb0b66022&metric=software_quality_maintainability_rating&token=sqb_4ef7409d8d3bb84ff51d945f5a62bc0df93895a9)](https://sonarqube.ennogelhaus.de/dashboard?id=gitroomhq_postiz-app_bd4cd369-af44-4d19-903b-c4bdb0b66022) [![Reliability Rating](https://sonarqube.ennogelhaus.de/api/project_badges/measure?project=gitroomhq_postiz-app_bd4cd369-af44-4d19-903b-c4bdb0b66022&metric=software_quality_reliability_rating&token=sqb_4ef7409d8d3bb84ff51d945f5a62bc0df93895a9)](https://sonarqube.ennogelhaus.de/dashboard?id=gitroomhq_postiz-app_bd4cd369-af44-4d19-903b-c4bdb0b66022) [![Security Rating](https://sonarqube.ennogelhaus.de/api/project_badges/measure?project=gitroomhq_postiz-app_bd4cd369-af44-4d19-903b-c4bdb0b66022&metric=software_quality_security_rating&token=sqb_4ef7409d8d3bb84ff51d945f5a62bc0df93895a9)](https://sonarqube.ennogelhaus.de/dashboard?id=gitroomhq_postiz-app_bd4cd369-af44-4d19-903b-c4bdb0b66022)
+</p>
+
 <div align="center">
   <strong>
   <h2>Your ultimate AI social media scheduling tool</h2><br />