xunit: define codefixes for SetAsserts

[Meir017]

The asserts defined in https://github.com/xunit/assert.xunit/blob/main/SetAsserts.cs

• Contains(T expected, ISet set) add support for xunit SetAsserts Contains #234
• Contains(T expected, IReadOnlySet set) add support for xunit SetAsserts Contains #234
• Contains(T expected, HashSet set) add support for xunit SetAsserts Contains #234
• Contains(T expected, ImmutableHashSet set) add support for xunit SetAsserts Contains #234
• DoesNotContains(T expected, ISet set) add support for xunit SetAsserts DoesNotContain #235
• DoesNotContains(T expected, IReadOnlySet set) add support for xunit SetAsserts DoesNotContain #235
• DoesNotContains(T expected, HashSet set) add support for xunit SetAsserts DoesNotContain #235
• DoesNotContains(T expected, ImmutableHashSet set) add support for xunit SetAsserts DoesNotContain #235
• ProperSubset(ISet expectedSubset, ISet? actual)
• ProperSuperset(ISet expectedSubset, ISet? actual)
• Subset(ISet expectedSubset, ISet? actual) add support for xunit SetAsserts Subset #236
• Superset(ISet expectedSubset, ISet? actual)

[Meir017]

• ProperSubset(ISet expectedSubset, ISet? actual)
• ProperSuperset(ISet expectedSubset, ISet? actual)
  related BeProperSubsetOf and BeProperSupersetOf fluentassertions#2363