Fix docs build errors

Fix shocco errors during docs generation

Closes-Bug: 1362691
Change-Id: I2b7fb008c89f0b4e7280b2d0a054320765e83e47
diff --git a/lib/nova b/lib/nova
index 14d07b0..853b697 100644
--- a/lib/nova
+++ b/lib/nova
@@ -677,7 +677,7 @@
 
     if [[ "$VIRT_DRIVER" = 'libvirt' ]]; then
         # The group **$LIBVIRT_GROUP** is added to the current user in this script.
-        # sg' will be used in run_process to execute nova-compute as a member of the
+        # ``sg`` is used in run_process to execute nova-compute as a member of the
         # **$LIBVIRT_GROUP** group.
         run_process n-cpu "$NOVA_BIN_DIR/nova-compute --config-file $compute_cell_conf" $LIBVIRT_GROUP
     elif [[ "$VIRT_DRIVER" = 'fake' ]]; then