Export struct sliceValidateError to allow error casting and rename it as (#2777)

SliceValidationError

Co-authored-by: Emeric de Bernis <emeric.debernis@adevinta.com>

binding/default_validator_benchmark_test.go

@@ -6,10 +6,10 @@ import (
 	"testing"
 )
 
-func BenchmarkSliceValidateError(b *testing.B) {
+func BenchmarkSliceValidationError(b *testing.B) {
 	const size int = 100
 	for i := 0; i < b.N; i++ {
-		e := make(sliceValidateError, size)
+		e := make(SliceValidationError, size)
 		for j := 0; j < size; j++ {
 			e[j] = errors.New(strconv.Itoa(j))
 		}