Fix parquet test_common feature flags

[tustvold]

Which issue does this PR close?

Closes #.

Rationale for this change

Without this running

cargo check -p parquet --features test_common

Would result in

error[E0433]: failed to resolve: could not find `test_util` in `util`
  --> parquet/src/util/test_common/file_util.rs:23:41
   |
23 |         PathBuf::from_str(&arrow::util::test_util::parquet_test_data()).unwrap();
   |                                         ^^^^^^^^^ could not find `test_util` in `util`

What changes are included in this PR?

Enables the arrow/test_util feature if the parquet test_common feature is enabled

Are there any user-facing changes?

No

[codecov-commenter]

Codecov Report

Merging #2003 (2eadea4) into master (c757829) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2003   +/-   ##
=======================================
  Coverage   83.58%   83.58%           
=======================================
  Files         222      222           
  Lines       57522    57522           
=======================================
+ Hits        48078    48079    +1     
+ Misses       9444     9443    -1     

Impacted Files	Coverage Δ
parquet_derive/src/parquet_field.rs	65.98% <0.00%> (ø)
parquet/src/encodings/encoding.rs	93.62% <0.00%> (+0.19%)	⬆️

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