jQuery selector string for Ajax table replacement is too generic

Problem/Motivation

The jQuery selector string used in the ajax_command_replace() call for replacing the ERVW widget table with updated values is too generic. It selects all <tbody> children elements. The selected entity IDs to be replaced may contain table HTML markup themselves, e.g. when extending the module behavior and displaying tabular content instead of the entity label. The result this case is the unexpected removal of the table body.

Proposed resolution

Use the ">" child combinator inside the ajax_command_replace() call.