Use a regex instead of splitting the URL on / etc

Library/Homebrew/resource_auditor.rb

@@ -104,7 +104,8 @@ module Homebrew
       return unless url.match?(%r{^https?://files\.pythonhosted\.org/packages/})
       return if name == owner.name # Skip the top-level package name as we only care about `resource "foo"` blocks.
 
-      pypi_package_name = url.split("/").last.split(/[-.]\d+?./).first.gsub(/[_.]/, "-")
+      url =~ %r{/(?<package_name>[^/]+)-}
+      pypi_package_name = Regexp.last_match(:package_name).gsub(/[_.]/, "-")
       return if name.casecmp(pypi_package_name).zero?
 
       problem "resource name should be `#{pypi_package_name}` to match the PyPI package name"