Fix: Replace 'source deactivate' with 'conda deactivate'

[Dasux]

changed the source deactivate line with conda deactivate

Context: /backend/script.sh had a deprecation error in my terminal when i ran it
source deactivate is old and no longer used... so i replaced it with conda deactivate

fix to this issue:-> #179
script.sh should run properly now

[Dasux]

mistake on my end...

we are using python's venv for virtual env creation, so conda deactivate mixes the two virtual environments

solution: just deactivate instead of conda deactivate is required