[REF] Ensure that any NULL values in the title field are fixed prior …

[seamuslee001]

…to changing the column

Overview

On a client site I found that they had a NULL value in a title_en_US column on civicrm_contribution_page and that the altering of the column to be required caused a DB error

Before

DB error

After

No DB Error

ping @eileenmcnaughton

[civibot]

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