Use py_binary with constants file, instead of arguments

[furtib]

Why:
I want to create a more organized, easily understandable alternative to #199.

Since there is a limit on the length of the arguments we can pass to our scripts, and passing many arguments makes things complicated, I decided to replace expand_template with a bazel_constants.json file.
This way, we can pass any number of arguments in an organized manner to the Python script.

What:

• Replaced the functionality of expand_template with a bazel_constant.json file for the per_file rule.

Addresses:
none