Update submodule public_regulated_data_types to latest Tue Feb 9 12:3…

…9:31 UTC 2021

    - public_regulated_data_types in PX4/Firmware (2772022): OpenCyphal/public_regulated_data_types@81526eb
    - public_regulated_data_types current upstream: OpenCyphal/public_regulated_data_types@7f5489e
    - Changes: OpenCyphal/public_regulated_data_types@81526eb...7f5489e

    7f5489e 2021-02-03 echoG - Adding a v0.2 for the uavcan battery (BMS) parameters and status (#105)
a26a29d 2021-01-17 Pavel Kirienko - Remove '.py' extension from the verification script to avoid conflicts when embedding this repository into Python projects (#101)
8ee6e6e 2021-01-17 Pavel Kirienko - Extend reg.drone.physics.kinematics with 3D geometry and define the GNSS service (#100)
359586e 2021-01-08 Pavel Kirienko - [DS-015] Formalize the port naming convention and restore the original unabbreviated namespace names (#98)
f07d09b 2021-01-08 Pavel Kirienko - Address design issues in uavcan.metatransport (#99)