chore: update version to 0.6.7-SNAPSHOT

Author: jtakakura

build.sbt

@@ -1,6 +1,6 @@
 lazy val commonSettings = Seq(
   organization := "com.nulabinc",
-  version      := "0.6.6",
+  version      := "0.6.7-SNAPSHOT",
   scalaVersion := "2.13.6",
   scalacOptions ++= Seq(
     "-deprecation",

src/main/resources/application.conf

@@ -1,6 +1,6 @@
 application {
   name = "Backlog Migration for Jira"
-  version = "0.6.6"
+  version = "0.6.7-SNAPSHOT"
   title = ${application.name} ${application.version} (c) nulab.inc
   fileName = backlog-migration-jira-${application.version}.jar
   product = "jira"