feat: abra release now asks for a release note

Before asking for a release note, it checks if release/next exists and
copies it to release/<tag>.

@@ -106,0 +126,4 @@
+  run git -C "$ABRA_DIR/recipes/$TEST_RECIPE" config --local user.name test
+  assert_success
+
+  run bash -c "echo 'those are some release notes for the next release' >> $ABRA_DIR/recipes/$TEST_RECIPE/release/next"

@@ -240,0 +262,4 @@
+			logrus.Debugf("dry run: move release note from 'next' to %s", tag)
+			return nil
+		}
+		err := os.Rename(nextReleaseNotePath, tagReleaseNotePath)