Add human readable Format for parquet ByteArray

[alamb]

Which issue does this PR close?

re #641

Rationale for this change

While working on #641 I found it challenging to determine what values were in what ByteArray while debugging with "{:?}"

What changes are included in this PR?

1. Add more human readable std::debug::Format impl for ByteArray

Before this PR the output for a string looks like this

ByteArray { data: Some(BufferPtr { data: [97, 110, 100, 111, 118, 101, 114], start: 0, len: 7, mem_tracker: None }) }

After this PR, the output looks like:

ByteArray { data: "andover" }

Are there any user-facing changes?

Debugging output is different for ByteArray

It also makes test failure output easier to understand:

---- column::writer::tests::test_byte_array_statistics stdout ----
thread 'column::writer::tests::test_byte_array_statistics' panicked at 'assertion failed: `(left == right)`
  left: `ByteArray { data: "lexington" }`,
 right: `ByteArray { data: "tewsbury" }`', parquet/src/column/writer.rs:1708:13
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

Rather than a list of individual bytes

[codecov-commenter]

Codecov Report

Merging #642 (087402a) into master (e84fe20) will increase coverage by 0.02%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master     #642      +/-   ##
==========================================
+ Coverage   82.47%   82.50%   +0.02%     
==========================================
  Files         167      168       +1     
  Lines       46454    47237     +783     
==========================================
+ Hits        38314    38972     +658     
- Misses       8140     8265     +125     

Impacted Files	Coverage Δ
parquet/src/data_type.rs	76.54% <0.00%> (-1.11%)	⬇️
arrow/src/array/equal_json.rs	88.69% <0.00%> (-2.52%)	⬇️
parquet/src/arrow/schema.rs	87.35% <0.00%> (-1.18%)	⬇️
arrow/src/datatypes/datatype.rs	66.08% <0.00%> (-0.74%)	⬇️
arrow/src/array/equal/mod.rs	93.45% <0.00%> (-0.48%)	⬇️
arrow/src/datatypes/field.rs	51.36% <0.00%> (-0.47%)	⬇️
arrow/src/array/builder.rs	85.97% <0.00%> (-0.29%)	⬇️
arrow/src/ipc/convert.rs	92.93% <0.00%> (-0.06%)	⬇️
arrow/src/json/reader.rs	83.99% <0.00%> (-0.04%)	⬇️
arrow/src/ipc/writer.rs	86.22% <0.00%> (ø)
... and 13 more

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