Disambiguating Space Adventure Cobra's Title Character

BUR #3688 has been approved by @evazion.

rename cobra -> cobra_(space_adventure_cobra)

Another character with an ambiguous name. His wiki even lists some other tags also named "Cobra", so this one should be disambiguated.

EDIT: The bulk update request #3688 (forum #174427) has been approved by @evazion.

The bulk update request #3688 (forum #174427) has been approved by @evazion.

Bump.

For future reference such requests should go to topic #17447.