Merge pull request #372 from domaframework/release

[Gradle Release Plugin] - pre tag commit:  '2.30.0-beta-5'.

Author: nakamura-to

gradle.properties

@@ -1,5 +1,5 @@
 group=org.seasar.doma
-version=2.30.0-beta-5-SNAPSHOT
+version=2.30.0-beta-5
 encoding=UTF-8
 systemProp.org.gradle.internal.publish.checksums.insecure=true
 projectUrl=https://github.com/domaframework/doma