Python function runtime provider doesn't run script hook

**Is your feature request related to a problem? Please describe.**
amplify-python-function-runtime-provider doesn't run script hook defined in root package.json

**Describe the solution you'd like**
amplify-nodejs-function-runtime-provider checks and runs script hook in root package.json, but python provider doesn't have the same behavior.

**Describe alternatives you've considered**
The script hook is defined on top-level package.json, it sounds the common behavior across all languages. If it is the language-specific hook, it should be defined inside of each function.

**Additional context**