adds badge to readme

Author: jonas-merkle

README.md

@@ -6,6 +6,7 @@ A collection of helper functions for the [Serilog.Extensions.Logging](https://ww
 
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+| Build & Test Status (main) | [![Build&Test](https://github.com/jjm-one/jjm.one.Serilog.Extensions.Logging.Helpers/actions/workflows/dotnet.yml/badge.svg)](https://github.com/jjm-one/jjm.one.Serilog.Extensions.Logging.Helpers/actions/workflows/dotnet.yml) |
 | Nuget Package Version | [![Nuget Version](https://img.shields.io/nuget/v/jjm.one.Serilog.Extensions.Logging.Helpers?style=flat-square)](https://www.nuget.org/packages/jjm.one.Serilog.Extensions.Logging.Helpers/) |
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