Fixed build workflow python command

Author: Adityya-K

.github/workflows/obc_build.yml

@@ -134,4 +134,5 @@ jobs:
 
     - name: Run HIL
       run: |
-          python hil/hil_main.py /dev/ttyACM0 OBC-firmware-crc.bin
+          cd hil
+          python hil_main.py /dev/ttyACM0 OBC-firmware-crc.bin