chore(deps): update dependency coverlet.msbuild to 6.0.3

Author: renovate[bot]

Diff for: Refit.Tests/Refit.Tests.csproj

@@ -19,7 +19,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="coverlet.msbuild" Version="6.0.2" />
+    <PackageReference Include="coverlet.msbuild" Version="6.0.3" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageReference Include="xunit" Version="2.9.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />