Remove useless shebang from main.py

[mtelka]

This solves the following issue:

$ src/pythonfinder/main.py
Traceback (most recent call last):
  File "/data/builds/pythonfinder/src/pythonfinder/main.py", line 8, in <module>
    from .cli import cli
ImportError: attempted relative import with no known parent package
$

by dropping the shebang and removing the execute mode from the file.