Fix link in "Vaadin Spring Tips" article (#11214)

Link to `3.0` branch of `vaadin/spring` which is the latest version for Vaadin 8 and latest version branch to contain this mentioned file with this path/name.

diff --git a/documentation/articles/VaadinSpringTips.asciidoc b/documentation/articles/VaadinSpringTips.asciidoc
index 58560bf034f632e41145e6ecf51132d02b3093bd..68751d42b6a0b382860d4c90723ece17108f1a63 100644 (file)
--- a/documentation/articles/VaadinSpringTips.asciidoc
+++ b/documentation/articles/VaadinSpringTips.asciidoc
@@ -22,4 +22,4 @@ example which can be configured:
 * `vaadin.servlet.closeIdleSessions=true`
 
 For full list of available properties, see
-https://github.com/vaadin/spring/blob/master/vaadin-spring-boot/src/main/java/com/vaadin/spring/boot/internal/VaadinServletConfigurationProperties.java[VaadinServletConfigurationProperties].
+https://github.com/vaadin/spring/blob/3.0/vaadin-spring-boot/src/main/java/com/vaadin/spring/boot/internal/VaadinServletConfigurationProperties.java[VaadinServletConfigurationProperties].