feat: pretty-printer for plan and expr (#90) 

feat: add __init__.py to builders package (#87) Added for `setuptools.find_packages()` to detect `substrait.builders` as a valid package.

chore(substrait): bump to v0.74.0 (#83) 

chore(substrait): bump to v0.56.0 (#62) 

chore(substrait): bump to v0.54.0 (#61) 

chore(substrait): bump to v0.52.0 (#60) Also updated the update script to automatically grab the latest tag from the upstream releases

chore(substrait): bump to v0.50.0 (#59) 

chore(substrait): bump to v0.49.0 (#58) 

chore(substrait): bump to v0.48.0 (#57) 

chore(substrait): bump to v0.47.0 (#56)