Bug 41334: Move modified_holds tables column settings under Tools section

Bug 36135 added new tool to batch modify holds and two new datatables.
Table holds_to_modify was added to "Table settings" page under section
Tools>Page: batch_hold_modification but table modified_holds is under
Circulation>Page: holds section. It should be also moved to Tools section.

To test:
1. Navigate to page "Table settings" and open section Circulation.
2. Jump to Page: holds.
=> Note that modified_holds tables settings are displayed under this page.
3. Apply this patch.
4. Open Tools section and jump to page batch_hold_modification.
=> Note that modified_holds tables settings are now displayed under this
page and they are no longer present under Circulation>Page: holds.

Sponsored-by: Koha-Suomi Oy
Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
(cherry picked from commit 05204294bb)
Signed-off-by: Jacob O'Mara <jacob.omara@openfifth.co.uk>

admin/columns_settings.yml

@@ -2165,27 +2165,6 @@ modules:
             -
               columnname: print_slip
 
-      modified_holds:
-        default_display_length: 20
-        columns:
-            -
-              columnname: expiration_date
-            -
-              columnname: title
-            -
-              columnname: barcode
-            -
-              columnname: patron
-            -
-              columnname: status
-            -
-              columnname: pickup_library
-            -
-              columnname: suspended
-            -
-              columnname: suspended_until
-            -
-              columnname: notes
     holdsratios:
       holds-ratios:
         default_display_length: 20
@@ -2685,6 +2664,27 @@ modules:
             -
               columnname: batch_hold_edit_note
 
+      modified_holds:
+        default_display_length: 20
+        columns:
+            -
+              columnname: expiration_date
+            -
+              columnname: title
+            -
+              columnname: barcode
+            -
+              columnname: patron
+            -
+              columnname: status
+            -
+              columnname: pickup_library
+            -
+              columnname: suspended
+            -
+              columnname: suspended_until
+            -
+              columnname: notes
     logviewer:
       logst:
         default_display_length: 20