Bump dotnet-sonarscanner from 5.15.0 to 6.0.0 (#257)

Author: dependabot[bot]

.config/dotnet-tools.json

@@ -3,10 +3,10 @@
   "isRoot": true,
   "tools": {
     "dotnet-sonarscanner": {
-      "version": "5.15.0",
+      "version": "6.0.0",
       "commands": [
         "dotnet-sonarscanner"
       ]
     }
   }
-}
+}