nuplan-devkit-v0.3

Version bump to nuPlan devkit v0.3

Feature list:

Metrics run time improvements @shakiba-motional @Noushin.Mehdipour
Refactored database models to improve test coverage @Rachel.Koh @Clarence.Chye
Add lane boundary API to the maps @christopher-motional
Model deployment pipeline @mspryn-motional
Reduce RAM usage @mspryn-motional
Devkit setup fixes @gianmarco-motional
nuBoard improvements @kokseang-motional
Improve simulation runtime @michael-noronha-motional
Kinematic bicycle model improvements @shakiba-motional
Enable LR schedulers @Hiok.Hian.Ong
IDM smart agents bugfix @patk-motional