Fix negated iteration wildcard filtering for boards [RUN AS-IF-FOSS]

What does this MR do?

Resolves #280781 (comment 580383176)

• Negated iteration wildcard filtering should use iterationWildcardId field when making GraphQL requests.

Please use :graphql_board_lists FF when testing. The filter should work regardless of the FF in boards (see demo).

• Refactors filter-related logic.

Screenshots (strongly suggested)

Screen_Recording_2021-06-01_at_2.11.57_PM

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