fix(DB): Add spawns for Tenris Mirkblood room in Karazhan.

[heyitsbench]

Changes Proposed:

This PR proposes changes to:

• Database (SAI, creatures, etc).

Issues Addressed:

• Closes (Events): Tenris Mirkblood's room is not spawned during Scourge Invasion. #16833

SOURCE:

The changes have been validated through:

• Sniffs (remember to share them with the open source community!)

Tests Performed:

This PR has been:

• Tested by repeatedly querying to DB.

Known Issues and TODO List:

• Mirkblood needs scripting, quest likely needs fixing.

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[Kitzunu]

I see I have messed something up

[heyitsbench]

Bearing in mind that normally I would use UPDATEs with the *_template tables, but 190610 does not exist in AC's DB and thus must be inserted.