modules documentation script: add anchor for '### Usage' sections
modules documentation script: add anchor for '### Usage' sections

So that they are unique.

Aerotenna/Firmware,mje-nz/PX4-Firmware,mcgill-robotics/Firmware,mcgill-robotics/Firmware,PX4/Firmware,PX4/Firmware,PX4/Firmware,krbeverx/Firmware,dagar/Firmware,Aerotenna/Firmware,PX4/Firmware,krbeverx/Firmware,mcgill-robotics/Firmware,acfloria/Firmware,PX4/Firmware,acfloria/Firmware,PX4/Firmware,acfloria/Firmware,mje-nz/PX4-Firmware,dagar/Firmware,krbeverx/Firmware,mje-nz/PX4-Firmware,Aerotenna/Firmware,mcgill-robotics/Firmware,Aerotenna/Firmware,acfloria/Firmware,dagar/Firmware,mje-nz/PX4-Firmware,acfloria/Firmware,krbeverx/Firmware,krbeverx/Firmware,acfloria/Firmware,krbeverx/Firmware,dagar/Firmware,krbeverx/Firmware,mcgill-robotics/Firmware,mcgill-robotics/Firmware,acfloria/Firmware,mje-nz/PX4-Firmware,dagar/Firmware,PX4/Firmware,mcgill-robotics/Firmware,mje-nz/PX4-Firmware,Aerotenna/Firmware,dagar/Firmware,Aerotenna/Firmware,Aerotenna/Firmware,dagar/Firmware,mje-nz/PX4-Firmware