ARROW-8467: [C++] Fix Array::View tests for big-endian platforms

[kiszk]

This PR adds the appropriate input on big-endian platform for test cases using ArrayFromJSON with fixed_size_binary.

I saw a problem with the following test:

TEST(TestArrayView, PrimitiveAsFixedSizeBinary) {
  auto arr = ArrayFromJSON(int32(), "[2020568934, 2054316386, null]");
  auto expected = ArrayFromJSON(fixed_size_binary(4), R"(["foox", "barz", null])");
  CheckView(arr, expected);
  CheckView(expected, arr);
}

Here, the expected strings are represented in binary as follows:

"foox" = [0x66 0x6f 0x6f 0x78]
"barz" = [0x62 0x61 0x72 0x7a]

This test gives a value as raw int32. The current values assume only a little-endian platform as follows to generate the expected binary sequence.

2020568934 = 0x786f6f66
2054316386 = 0x7a726162

IMHO, for big-endian platform, the following value should be given

1718579064 = 0x666f6f78
1650553466 = 0x6261727a

These tests have the above problems:
TEST_F(TestChunkedArray, View) at https://github.com/apache/arrow/blob/master/cpp/src/arrow/table_test.cc#L175
TEST(TestArrayView, PrimitiveAsFixedSizeBinary) at https://github.com/apache/arrow/blob/master/cpp/src/arrow/array_view_test.cc#L105
TEST(TestArrayView, StructAsStructSimple) at https://github.com/apache/arrow/blob/master/cpp/src/arrow/array_view_test.cc#L126
TEST(TestArrayView, ExtensionType) at https://github.com/apache/arrow/blob/master/cpp/src/arrow/array_view_test.cc#L393

[github-actions]

https://issues.apache.org/jira/browse/ARROW-8467

[pitrou]

+1, thank you