[skip ci] Release v4.0.0

Author: puneetbehl

gradle.properties

@@ -3,7 +3,7 @@ grailsGradlePluginVersion=5.1.0
 groovyVersion=3.0.7
 liquibaseVersion=4.6.2
 liquibaseHibernateVersion=4.6.1
-projectVersion=4.0.0-SNAPSHOT
+projectVersion=4.0.0
 
 websiteUrl=https://grails-plugins.github.io/grails-database-migration
 issueTrackerUrl=https://github.com/grails-plugins/grails-database-migration/issues