Future runbot improvement may share sources between build, meaning that sources will be readonly to avoid any interaction. _touch() was supposed to handle ro filesystem butf7130556introduced a new test that was not working in this case. Instead of trying to touch file and pseudomocking the result if the filesystem is readonly, this commit add a real patch on getmtime. cherry-pick ofb295723c99closes odoo/odoo#34823 Signed-off-by: Xavier Dollé (xdo) <xdo@odoo.com>