bump version in documentation

Author: Baptiste Noleau

charts/dso-grafana/README.md

@@ -1,6 +1,6 @@
 # dso-grafana
 
-![Version: 1.5.1](https://img.shields.io/badge/Version-1.5.1-informational?style=flat-square) ![Type: application](https://img.shields.io/badge/Type-application-informational?style=flat-square)
+![Version: 1.5.2](https://img.shields.io/badge/Version-1.5.2-informational?style=flat-square) ![Type: application](https://img.shields.io/badge/Type-application-informational?style=flat-square)
 
 This Helm chart deploy Grafana instances and default dashboards for each projects read from values file.