Find and use Python 2 (#5442)
Find and use Python 2 (#5442)

This will make the build works in distros that have Python 3 as default
and will not break anything in distros that have Python 2 as default.
mcgill-robotics/Firmware,darknight-007/Firmware,mje-nz/PX4-Firmware,jlecoeur/Firmware,acfloria/Firmware,acfloria/Firmware,Aerotenna/Firmware,mje-nz/PX4-Firmware,krbeverx/Firmware,jlecoeur/Firmware,mje-nz/PX4-Firmware,mcgill-robotics/Firmware,jlecoeur/Firmware,mje-nz/PX4-Firmware,dagar/Firmware,Aerotenna/Firmware,krbeverx/Firmware,acfloria/Firmware,darknight-007/Firmware,jlecoeur/Firmware,mje-nz/PX4-Firmware,mcgill-robotics/Firmware,Aerotenna/Firmware,acfloria/Firmware,Aerotenna/Firmware,darknight-007/Firmware,dagar/Firmware,jlecoeur/Firmware,darknight-007/Firmware,jlecoeur/Firmware,PX4/Firmware,krbeverx/Firmware,dagar/Firmware,Aerotenna/Firmware,dagar/Firmware,Aerotenna/Firmware,dagar/Firmware,PX4/Firmware,PX4/Firmware,acfloria/Firmware,acfloria/Firmware,PX4/Firmware,PX4/Firmware,mcgill-robotics/Firmware,PX4/Firmware,krbeverx/Firmware,PX4/Firmware,mje-nz/PX4-Firmware,jlecoeur/Firmware,krbeverx/Firmware,mcgill-robotics/Firmware,mcgill-robotics/Firmware,krbeverx/Firmware,dagar/Firmware,krbeverx/Firmware,mcgill-robotics/Firmware,dagar/Firmware,Aerotenna/Firmware,darknight-007/Firmware,mje-nz/PX4-Firmware,acfloria/Firmware,jlecoeur/Firmware