Cool, good luck! If you end up wanting a more 'official' STLink probe which is still pretty cheap, the ones on their 'discovery kit' and larger 'nucleo' boards can be disconnected from the main board and used with other targets.
They're a little bulky, but if you're interested in bare-metal programming, the embedded Rust ebook[1] currently uses an STM32F3 discovery kit[2] as a target, and that board's user manual has instructions for using its ST-Link to program/debug an external application[3] like your drone.