Add Hashset (#1) * feat: in memory implementation * feat: redis implementation * test: add tests for AddAsync * test: add tests for AddAsync + RemoveAsync * test: add tests for ContainsAsync * test: add tests for CountAsync * test: add tests for LongCountAsync * test: refactor redis tests to dispose ephemeral db * test: add test for ClearAsync * chore: update ephemerally * test: fix redis tests to actually dispose ephemeral db * test: add test for IAsyncEnumerable * chore: ci workflows * chore: remove unused usings * chore: fix redis test project dir * chore: ci changes * chore: ci changes * chore: push to nuget.org