Update dependency Microsoft.AspNetCore.SignalR.Client to 8.0.19

Author: dependencyupdates[bot]

src/Directory.Packages.props

@@ -18,7 +18,7 @@
     <PackageVersion Include="GitHubActionsTestLogger" Version="2.4.1" />
     <PackageVersion Include="HdrHistogram" Version="2.5.0" />
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="8.0.17" />
-    <PackageVersion Include="Microsoft.AspNetCore.SignalR.Client" Version="8.0.17" />
+    <PackageVersion Include="Microsoft.AspNetCore.SignalR.Client" Version="8.0.19" />
     <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="8.0.1" />
     <PackageVersion Include="Microsoft.Extensions.DependencyModel" Version="8.0.2" />
     <PackageVersion Include="Microsoft.Extensions.Hosting" Version="8.0.1" />