get_dependencies() refactor (v2) (#1825)

* add extra readme help steps

* more readme updates

* bugfix: add enhanced-monitoring role-policy-attachment to rds dependencies

* rename get_dependencies() function name

* re-add paramater_group_name (was accidentally deleted)

* use arrays correctly

* comply w/ 79 char limit

* syntax changes

* continued syntax changes

* yet more syntax changes

* more syntax changes

* more refactoring

* remove bug fix

* comment typo

* missed a spot

* comment typos

* fix usage of _find_resource_()

* revert getting names of tf-resources from _find_resource_()

* add typehints

* change type hint

* removed unused mypy types

* char limit

* flake8 compliance

* uncomment token

* move import for flake

* use Iterable

* 79 char limit