Bump vaadin-bom from 14.6.1 to 14.6.8 in /dcat-suite-app

Bumps vaadin-bom from 14.6.1 to 14.6.8.

---
updated-dependencies:
- dependency-name: com.vaadin:vaadin-bom
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

dcat-suite-app/pom.xml

@@ -13,7 +13,7 @@
 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 		<packaging.type>jar</packaging.type>
 
-		<vaadin.version>14.6.1</vaadin.version>
+		<vaadin.version>14.6.8</vaadin.version>
 		<!-- <spring-boot.version>2.3.3.RELEASE</spring-boot.version> -->