Poetry deps w/ python version and platform, and multiple constraints dependencies (#592)

* poetry deps w/ python version and platform and multiple constraints dependencies

* add regr test for databricks-sql-connector

* fix parse_python_version (drop patch), w/ tests

* add support 1 digit to parse_python_version

* fix or->and, fix doctests, refact test_combine_conda_selectors

* update langchain snapshot test

* add "or" support

* wrap again python selector if there is an "or" and platform specified

* add one test for python version in "or"

* add "~=" and ".*" support

Author: lorepirri