build: upgrade json-migration-helper to 0.9.1

Author: javier-godoy

pom.xml

@@ -137,7 +137,7 @@
 		<dependency>
 			<groupId>com.flowingcode.vaadin</groupId>
 			<artifactId>json-migration-helper</artifactId>
-			<version>0.9.0</version>
+			<version>0.9.1</version>
 		</dependency>
 		<dependency>
 			<groupId>org.slf4j</groupId>