[IMP] accounting: change the lock date warning to an optional tip

task-3787113

closes #9165

X-original-commit: 5c84c9f
Signed-off-by: Xavier Platteau (xpl) <xpl@odoo.com>

content/applications/finance/accounting/reporting/year_end.rst

@@ -101,8 +101,9 @@ correctly reporting a balance of zero. If that is the case, set an :guilabel:`Al
 to the last day of the fiscal year by going to :menuselection:`Accounting --> Accounting --> Lock
 Dates`.
 
-.. warning::
-   Setting an :guilabel:`All Users Lock Date` is **irreversible** and cannot be removed.
+.. tip::
+   Install the :guilabel:`Irreversible Lock Date` (`account_lock`) module to make the :guilabel:`All
+   Users Lock Date` *irreversible* once set.
 
 .. note::
    A specific year-end closing entry is **optional** in order to close out the **profit and loss