docs(sensing): update lidar data field requirement

[KYabuuchi]

Description

• I noticed that the lidar data filed types presented on this page do not match the actual ones. So, I fixed them.

type	before	after	reference
T(time)	FLOAT32	FLOAT64	distortion_corrector.cpp
I(intensity)	UINT8	FLOAT32	ring_outlier_filter.cpp

• Also, I found some nodes require the time_stamp as seconds rather than nanoseconds.
  e.g. distortion_corrector.cpp, nebula_common.cpp

• This is trivial, but the default T's name is time_stamp, not time, so I corrected some notations.
  e.g. utility/utilities.cpp, nebula_common/point_types.hpp

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[github-actions]

Documentation URL: https://autowarefoundation.github.io/autoware-documentation/pr-478/
Modified URLs:

• https://autowarefoundation.github.io/autoware-documentation/pr-478/design/autoware-architecture/sensing/data-types/point-cloud/

[drwnz]

@KYabuuchi I think we can merge this for now, but we actually plan to change the point cloud types to the ones in the current documentation in the near future. But we can change back when this happens, to avoid confusion.
@xmfcx does this sound OK to you?

[KYabuuchi]

When the point cloud type is updated, we revert this or update. Thanks everyone. 😄