RawEquals: Sets with the same unknowns are equal enough for RawEquals

[mildwonkey]

RawEquals should return true when comparing sets with the same type and same unknown values.

I've copied all the tests from Equal (modified to match the expected result of RawEquals) - the only test that was failing before this change is this one:

		{
			ObjectVal(map[string]Value{
				"a": SetVal([]Value{
					ObjectVal(map[string]Value{
						"b": UnknownVal(String),
					}),
				}),
			}),
			ObjectVal(map[string]Value{
				"a": SetVal([]Value{
					ObjectVal(map[string]Value{
						"b": UnknownVal(String),
					}),
				}),
			}),
			true,
		},

I've also verified that this change doesn't cause any test failures in terraform.

[codecov]

Codecov Report

Merging #64 into master will increase coverage by 0.32%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master      #64      +/-   ##
==========================================
+ Coverage   70.85%   71.17%   +0.32%     
==========================================
  Files          79       79              
  Lines        7284     7276       -8     
==========================================
+ Hits         5161     5179      +18     
+ Misses       1670     1654      -16     
+ Partials      453      443      -10     

Impacted Files	Coverage Δ
cty/value_ops.go	86.15% <100.00%> (+2.45%)	⬆️
cty/marks.go	80.98% <0.00%> (+1.40%)	⬆️
cty/convert/compare_types.go	100.00% <0.00%> (+7.14%)	⬆️

---

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[apparentlymart]

Thanks! This makes sense to me, and fixes the bug I introduced in my latest changes.