Closed topics missing _bbp_status post meta key

[netweb]

Some 'closed' topics are missing the _bbp_status = publish meta key.

A topic's _bbp_status only exists if the topic is closed with status publish (It does not exist if post_status = publish)

Occurrences:

1. When creating a new topic and including the status 'closed' post meta key _bbp_status is not created.

2. Previously imported closed topics were not assigned the _bbp_status = publish meta key.

Extra Issues:

1. Currently if a closed topic is missing it's _bbp_status meta key we cannot update the status meta.

ToDo:

1. Update bbp_close_topic() to allow _bbp_status to be added to existing post_status = closed topics

2. Update repair tools to repair closed topics missing _bbp_status meta key

3. Add bbPress 2.6 database upgrade routine we should update closed topics where post_status = closed and meta bbp_status = publish does not exist.

Related: #2577 Imported closed/locked topics missing 'publish' postmeta _bbp_status