[BUG] Fix mobile UI for organisation creation

- Don't make checkpoints or radio inputs full width on a small screen,
these obviously shouldn't try to take up the whole width of a container.
- Wrap the label for organisation permission box inside a `<span
class="inline field">`, so it gets a left-margin from the `.inline.field
> :first-child` selector. This make the checkboxes and radio buttons
groups look indented from the left.
- Resolves #4361

web_src/css/form.css

@@ -466,7 +466,7 @@ textarea:focus,
     margin-bottom: 1em;
     width: 100%;
   }
-  .new.org .ui.form .field input {
+  .new.org .ui.form .field input:not([type="checkbox"], [type="radio"]) {
     width: 100% !important;
   }
 }