refactor(perception): rename TrafficSignal** to TrafficLight**

[ktro2828]

Description

This PR renames the autoware_perception_msgs/msg/TrafficSignal** to TrafficLight**.

TODO: some elements in target messages should be updated

Related links

• TIER IV INTERNAL LINK1
• TIER IV INTERNAL LINK2

Tests performed

Notes for reviewers

Interface changes

Effects on system behavior

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[stale]

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