Adding net7.0 target framework

Author: maximn

GoogleMapsApi/GoogleMapsApi.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-	<TargetFrameworks>net8.0;net6.0;netstandard2.0</TargetFrameworks>
+	<TargetFrameworks>net8.0;net7.0;net6.0;netstandard2.1</TargetFrameworks>
 	<LangVersion>latest</LangVersion>
 	<Version>0.0.0</Version>
 	<AppxAutoIncrementPackageRevision>True</AppxAutoIncrementPackageRevision>