Use HTTPS for external links where possible
See
@@ -72,7 +72,7 @@ If you want to jump straight in, a number of sample applications are available:
| {samples}/junit5[JUnit 5]
| Gradle
-| Demonstrates the use of Spring REST Docs with http://junit.org/junit5/[JUnit 5].
+| Demonstrates the use of Spring REST Docs with https://junit.org/junit5/[JUnit 5].
|===
