Premailer shouldn't remove script tags from our emails

Closes #14943.

config/initializers/premailer.rb

@@ -3,5 +3,6 @@ Premailer::Rails.config.merge!(
   generate_text_part: false,
   preserve_styles: true,
   remove_comments: true,
-  remove_ids: true
+  remove_ids: true,
+  remove_scripts: false
 )

spec/mailers/shared/notify.rb

@@ -141,10 +141,12 @@ shared_examples 'a new user email' do
 end
 
 shared_examples 'it should have Gmail Actions links' do
+  it { is_expected.to have_body_text '<script type="application/ld+json">' }
   it { is_expected.to have_body_text /ViewAction/ }
 end
 
 shared_examples 'it should not have Gmail Actions links' do
+  it { is_expected.to_not have_body_text '<script type="application/ld+json">' }
   it { is_expected.to_not have_body_text /ViewAction/ }
 end