Update config for Alpine 3.9

Christopher Horrell · Christopher Horrell · commit c31ec45ea0bf · 2019-01-31T09:54:40.000-05:00
diff --git a/config b/config
@@ -1,4 +1,4 @@
 baseuri     https://nodejs.org/dist
 default_variant stretch
-alpine_version  3.8
+alpine_version  3.9
 debian_versions jessie stretch
