feat(autoware_adapi_v1_msgs): remove planning factor type

[isamu-takagi]

Description

Remove the type field used in the proposed message (this is before the release).
The latest proposal uses behavior field instead.

Tests performed

See autowarefoundation/autoware.universe#5793.

Effects on system behavior

Not applicable.

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[mitsudome-r]

NOTE
The strings for behavior field are defined in this message:
https://github.com/autowarefoundation/autoware_adapi_msgs/blob/main/autoware_adapi_v1_msgs/planning/msg/PlanningBehavior.msg