fix(datastore): fix NoIndex for array property

[aaron0x]

When converting proto to Entity with array property, ExcludeFromIndexes appears in the values level, not the top level.

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[bhshkh]

Suggested change

	if !testutil.Equal(want, dst) {
	t.Errorf("NoIndex should be correct: compare:\ngot: %#v\nwant: %#v", dst, want)
	}
	cmpProperties := func(p1, p2 Property) bool {
	return p1.Name < p2.Name
	}
	if !testutil.Equal(want.Properties, dst.Properties, cmpopts.SortSlices(cmpProperties)) {
	t.Errorf("NoIndex should be correct: Property:\ngot: %#v\nwant: %#v", dst, want)
	}
	if !testutil.Equal(want.Key, dst.Key) {
	t.Errorf("NoIndex should be correct: Key:\ngot: %#v\nwant: %#v", dst, want)
	}

[bhshkh]

This fails intermittently with error:

=== RUN   TestLoadArrayIndex
    load_test.go:657: NoIndex should be correct: compare:
        got:  &datastore.Entity{Key:(*datastore.Key)(0xc0005457c0), Properties:[]datastore.Property{datastore.Property{Name:"non-indexed", Value:[]interface {}{"3", "4"}, NoIndex:true}, datastore.Property{Name:"indexed", Value:[]interface {}{"1", "2"}, NoIndex:false}}}
        want: &datastore.Entity{Key:(*datastore.Key)(0xc0004b1b80), Properties:[]datastore.Property{datastore.Property{Name:"indexed", Value:[]interface {}{"1", "2"}, NoIndex:false}, datastore.Property{Name:"non-indexed", Value:[]interface {}{"3", "4"}, NoIndex:true}}}
--- FAIL: TestLoadArrayIndex (0.00s)

Please see suggested changes.

[aaron0x]

thanks for the suggestion.