Update README.md

Author: chrislyzztest

README.md

@@ -2,5 +2,5 @@
 An OpenID Connect setup with Angular 5, IdentityServer 4 and ASP.NET Core resource api.
 These solutions are used as material for a blog series about OpenID connect.
 
-Part 1: http://blog.christianlydemann.com/post/openid-connect-part1/
+Part 1: https://blog.christianlydemann.com/post/openid-connect-part1-openid-connect-overview/