README : fix shield : removed Windows icon -> MinGW

simple-icons/simple-icons#10019

Author: thomaslepoix

README.md

@@ -8,7 +8,7 @@
 [![SonarCloud quality gate](https://sonarcloud.io/api/project_badges/measure?project=thomaslepoix_Qucs-RFlayout&metric=alert_status)](https://sonarcloud.io/dashboard?id=thomaslepoix_Qucs-RFlayout)
 
 [![Package Debian](https://img.shields.io/github/actions/workflow/status/thomaslepoix/Qucs-RFlayout/release-debian.yml?label=package&logo=debian)](https://software.opensuse.org/download.html?project=home:thomaslepoix:open-rflab&package=qucsrflayout)
-[![Package Windows](https://img.shields.io/github/actions/workflow/status/thomaslepoix/Qucs-RFlayout/release-windows.yml?label=package&logo=windows)](https://github.com/thomaslepoix/Qucs-RFlayout/releases)
+[![Package Windows](https://img.shields.io/github/actions/workflow/status/thomaslepoix/Qucs-RFlayout/release-windows.yml?label=package&logo=mingww64)](https://github.com/thomaslepoix/Qucs-RFlayout/releases)
 
 # Qucs-RFlayout