chore: add test on plugin

Author: matthv

packages/forest_admin_datasource_customizer/spec/lib/forest_admin_datasource_customizer/plugins/plugin_spec.rb

@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+module ForestAdminDatasourceCustomizer
+  module Plugins
+    describe Plugin do
+      let(:plugin) { described_class.new }
+
+      describe '#run' do
+        it 'raises NotImplementedError by default' do
+          expect do
+            plugin.run(DatasourceCustomizer.new)
+          end.to raise_error(NotImplementedError, /has not implemented method 'run'/)
+        end
+      end
+    end
+  end
+end