write-skew Doc Feedback

https://access.qa.redhat.com/documentation/en-us/red_hat_data_grid/7.3/html-single/red_hat_data_grid_user_guide/index#tx_write_skew

The attribute is deprecated, but it is not there (I've checked C/S mode only by now).
So the deprecation might be confusing to users

Anyway, the description should be
write skew is automatically enabled for for Repeatable Read + Optimistic locking
and this is the default for embedded mode !

Otherwise it will be disabled.