Enable all pylint checks.

[garrison]

What is the expected enhancement?

Currently, a number of pylint checks are disabled throughout the code base. As we improve the code, we should either fix each check or disable it locally, in preparation for potential contribution to qiskit-optimization.

• fixme
• invalid-name
• too-few-public-methods
• missing-function-docstring
• protected-access (waiting on Improve magic rounding to work with all available encodings #7)
• redefined-outer-name
• no-member
• pointless-statement
• too-many-locals
• useless-super-delegation
• consider-using-f-string
• too-many-statements
• too-many-branches
• consider-using-enumerate
• duplicate-code
• docstring plugin tests (temporarily disabled in de3bf52)

Currently disabled within notebooks only

• wrong-import-order
• wrong-import-position (seems irrelevant, actually)
• line-too-long