chore(js-tookit): configure tag prefix for changelog-generator

Without this, we'll get the wrong tag name in the changelog.

In the next commit I'm going to do something similar for Lerna.

Author: wincent

maintenance/projects/js-toolkit/.yarnrc

@@ -0,0 +1,5 @@
+# Note that even though this project currently uses Lerna to produce releases,
+# we still have this .yarnrc file for consistency with the other projects, and
+# so that @liferay/changelog-generator can derive the tag format from it.
+version-tag-prefix "liferay-js-toolkit/v"
+version-git-message "chore: prepare liferay-js-toolkit/%s release"