Only apply not many requests to requestable bodies

Our main intent with this tag is for it to act as a hook for suggesting
some good basic requests to "bootstrap transparency". There's no point
in doing this if users can't make requests to the body.

app/models/public_body.rb

@@ -1002,10 +1002,14 @@ def missing_email?
   end
 
   def update_not_many_requests_tag
-    if info_requests.is_searchable.size < not_many_public_requests_size
+    if is_requestable? && not_many_public_requests?
       add_tag_if_not_already_present('not_many_requests')
     else
       remove_tag('not_many_requests')
     end
   end
+
+  def not_many_public_requests?
+    info_requests.is_searchable.size < not_many_public_requests_size
+  end
 end

app/views/admin_public_body/_form.html.erb

@@ -70,7 +70,7 @@
 
       <ul>
         <li><code>missing_email</code> users can help source missing request addresses via a <%= link_to 'public search', list_public_bodies_by_tag_path('missing_email') %>.</li>
-        <li><code>not_many_requests</code> users can find low-transparency bodies via a <%= link_to 'public search', list_public_bodies_by_tag_path('not_many_requests') %>.</li>
+        <li><code>not_many_requests</code> users can find low-transparency bodies via a <%= link_to 'public search', list_public_bodies_by_tag_path('not_many_requests') %>. Only applied to bodies that are requestable.</li>
       </ul>
     </div>
   </div>

spec/models/public_body_spec.rb

@@ -255,6 +255,18 @@
         expect(public_body).not_to be_tagged('not_many_requests')
       end
     end
+
+    context 'when a not_requestable body is is tagged not_many_requests' do
+      let!(:public_body) { FactoryBot.create(:public_body) }
+
+      before { public_body.add_tag_if_not_already_present('not_many_requests') }
+      before { public_body.update(request_email: '') }
+
+      it 'removes the not many requests tag' do
+        subject
+        expect(public_body).not_to be_tagged('not_many_requests')
+      end
+    end
   end
 
   describe '#name' do