Optimization of some functions

[hrshdhgd]

Addresses #202

• [x] Ran poetry update
• [x] Call _get_sssom_schema_object() once in the function get_dict_from_mapping() rather than multiple times in a for loop that is inefficient.
• [x] Instead of pandas.iterrows() use pandas.apply() in _get_mapping_set_from_df()
• [x] Use dict/list comprehensions instead of for loops
• [x] Use sets instead of lists where lookups are done and sequence of elements don't matter.
• [x] Improve SchemaView object instantiation and persistence
  • [x] Use @cached_property thank you @cthoyt

[joeflack4]

I glanced through quickly and couldn't figure out how things are running faster, but glad to hear it!