ARROW-8506: [C++] Add tests to verify the encoded stream of RLE with bit_width > 8

[kiszk]

This PR adds test cases to verify whether the encoded values are stored in a little-endian format when RLE with bit_width > 8 is applied. Parquet encoder/decoder handles the value as little-endian as follows:
https://github.com/apache/parquet-mr/blob/master/parquet-column/src/main/java/org/apache/parquet/column/values/rle/RunLengthBitPackingHybridEncoder.java#L244
https://github.com/apache/parquet-mr/blob/master/parquet-column/src/main/java/org/apache/parquet/column/values/rle/RunLengthBitPackingHybridDecoder.java#L87

There is no test of this type in the current test cases of Rle.

[github-actions]

https://issues.apache.org/jira/browse/ARROW-8506

[kiszk]

retest this please

[kiszk]

The failures may not be related to this PR.

       8: github.com/minio/minio@/cmd/fs-v1-helpers.go:320:cmd.fsCreateFile()
       7: github.com/minio/minio@/cmd/fs-v1.go:973:cmd.(*FSObjects).putObject()
       6: github.com/minio/minio@/cmd/fs-v1.go:887:cmd.(*FSObjects).PutObject()
       5: github.com/minio/minio@/cmd/config-common.go:62:cmd.saveConfig()
       4: github.com/minio/minio@/cmd/config-encrypted.go:291:cmd.migrateConfigPrefixToEncrypted()
       3: github.com/minio/minio@/cmd/config-encrypted.go:107:cmd.handleEncryptedConfigBackend()
       2: github.com/minio/minio@/cmd/server-main.go:194:cmd.initSafeMode()
       1: github.com/minio/minio@/cmd/server-main.go:447:cmd.serverMain()
/arrow/cpp/src/arrow/filesystem/s3fs_test.cc:731: Failure
Failed
'OutcomeToStatus(client_->CreateBucket(req))' failed with IOError: AWS Error [code 100]: Unable to parse ExceptionName: XMinioServerNotInitialized Message: Server not initialized, please try again. with address : 127.0.0.1
[  FAILED  ] TestS3FSGeneric.OpenInputFile (6041 ms)
[----------] 18 tests from TestS3FSGeneric (108737 ms total)

[----------] Global test environment tear-down
[==========] 39 tests from 4 test cases ran. (230555 ms total)
[  PASSED  ] 1 test.
[  FAILED  ] 38 tests, listed below:
[  FAILED  ] TestMinioServer.Connect
[  FAILED  ] TestS3FS.GetFileInfoRoot
[  FAILED  ] TestS3FS.GetFileInfoBucket
[  FAILED  ] TestS3FS.GetFileInfoObject
[  FAILED  ] TestS3FS.GetFileInfoSelector
[  FAILED  ] TestS3FS.GetFileInfoSelectorRecursive
[  FAILED  ] TestS3FS.CreateDir
[  FAILED  ] TestS3FS.DeleteFile
[  FAILED  ] TestS3FS.Move
[  FAILED  ] TestS3FS.OpenInputStream
[  FAILED  ] TestS3FS.OpenInputFile
[  FAILED  ] TestS3FS.OpenOutputStreamBackgroundWrites
[  FAILED  ] TestS3FS.OpenOutputStreamSyncWrites
[  FAILED  ] TestS3FS.OpenOutputStreamAbortBackgroundWrites
[  FAILED  ] TestS3FS.OpenOutputStreamAbortSyncWrites
[  FAILED  ] TestS3FS.OpenOutputStreamDestructorBackgroundWrites
[  FAILED  ] TestS3FS.OpenOutputStreamDestructorSyncWrite
[  FAILED  ] TestS3FS.FileSystemFromUri
[  FAILED  ] TestS3FSGeneric.Empty
[  FAILED  ] TestS3FSGeneric.NormalizePath
[  FAILED  ] TestS3FSGeneric.CreateDir
[  FAILED  ] TestS3FSGeneric.DeleteDir
[  FAILED  ] TestS3FSGeneric.DeleteDirContents
[  FAILED  ] TestS3FSGeneric.DeleteFile
[  FAILED  ] TestS3FSGeneric.DeleteFiles
[  FAILED  ] TestS3FSGeneric.MoveFile
[  FAILED  ] TestS3FSGeneric.MoveDir
[  FAILED  ] TestS3FSGeneric.CopyFile
[  FAILED  ] TestS3FSGeneric.GetFileInfo
[  FAILED  ] TestS3FSGeneric.GetFileInfoVector
[  FAILED  ] TestS3FSGeneric.GetFileInfoSelector
[  FAILED  ] TestS3FSGeneric.GetFileInfoSelectorWithRecursion
[  FAILED  ] TestS3FSGeneric.OpenOutputStream
[  FAILED  ] TestS3FSGeneric.OpenAppendStream
[  FAILED  ] TestS3FSGeneric.OpenInputStream
[  FAILED  ] TestS3FSGeneric.OpenInputFile

38 FAILED TESTS
/build/cpp/src/arrow/filesystem


99% tests passed, 1 tests failed out of 86
...
The following tests FAILED:
	 76 - arrow-s3fs-test (Failed)

[pitrou]

This looks good to me, thank you. I've restarted the failing CI builds.

[pitrou]

CI failures are unrelated, merging.