Changed to error message when signing assembly not found.
Changed to error message when signing assembly not found.

Microsoft/ApplicationInsights-aspnetcore,Microsoft/ApplicationInsights-aspnet5,Microsoft/ApplicationInsights-aspnetcore,Microsoft/ApplicationInsights-aspnet5,Microsoft/ApplicationInsights-aspnetcore,gzepeda/ApplicationInsights-aspnetcore,gzepeda/ApplicationInsights-aspnetcore,gzepeda/ApplicationInsights-aspnetcore,Microsoft/ApplicationInsights-aspnet5