fix(deploy): properly detect when pkg names is ""

empty strings evaluate to true, so this was falsely using
empty strings for package names

deploy/run.rb

@@ -21,7 +21,7 @@ def run_for_packages
 end
 
 def package_names
-  return ENV["PACKAGE_NAMES"].split(",") if ENV["PACKAGE_NAMES"]
+  return ENV["PACKAGE_NAMES"].split(",") unless ENV["PACKAGE_NAMES"]&.empty?
 
   [ENV["PACKAGE_NAME"]]
 end