Revert "grub module: fix efiInstallAsRemovable description"

This reverts commit c2b5662.
It broke creating the manual.  I suspect the descriptions are
auto-wrapped by <para> and </para>.

We've been through this already in 3af715a.
/cc #24978, @zraexy, @Mic92.

nixos/modules/system/boot/loader/grub/grub.nix

@@ -383,7 +383,7 @@ in
         default = false;
         type = types.bool;
         description = ''
-          <para>Whether to invoke <literal>grub-install</literal> with
+          Whether to invoke <literal>grub-install</literal> with
           <literal>--removable</literal>.</para>
 
           <para>Unless you turn this on, GRUB will install itself somewhere in
@@ -412,7 +412,7 @@ in
             the NVRAM state of the computer (like a USB "removable" drive)</para></listitem>
             <listitem><para>You simply dislike the idea of depending on NVRAM
             state to make your drive bootable</para></listitem>
-          </itemizedlist></para>
+          </itemizedlist>
         '';
       };