Update dependency org.codehaus.mojo:flatten-maven-plugin to v1.7.3

Author: xdev-renovate

vaadin-simple-grid-filter/pom.xml

@@ -198,7 +198,7 @@
 					<plugin>
 						<groupId>org.codehaus.mojo</groupId>
 						<artifactId>flatten-maven-plugin</artifactId>
-						<version>1.7.2</version>
+						<version>1.7.3</version>
 						<configuration>
 							<flattenMode>ossrh</flattenMode>
 						</configuration>