Updated to 3.10

- Updated all leader traits to include the new consolidated leader classes.

- Updated portrait asset selectors to include the new consolidated leader classes.

- Updated portraits to accommodate the changes in leader classes.

- The special and specific portraits that use the defunct general leader class to appear in the portrait pool will now use the general subclass trait instead.

NOTE: This update is just a placeholder and hotfix for leaders retiring.

There are still more updates to come once I redo the portrait assets to accommodate the changes made to leaders from this recent Stellaris update 3.10.

This also applies to the other Halo portrait mods.

- Changed the old leader_age modifier to leader_lifespan_add for all Covenant species to prevent immediate retirement or death at the start of the game.