Disable parquet vectored reads to fix gcs-connector incompatibility

[kellen]

Summary

• Disables parquet-hadoop vectored reads via parquet.hadoop.vectored.io.enabled=false in core-site.xml
• gcs-connector 3.1.16 calls VectoredReadUtils.validateRangeRequest(FileRange) expecting a void return, but hadoop-common 3.4.3 changed the return type to FileRange, causing NoSuchMethodError at runtime when parquet-hadoop attempts vectored reads through GoogleHadoopFileSystem
• This affects the legacy HadoopFormatIO read path (used when UseSplittableDoFn=false)

Test plan

• Reproduced via integration test in Add integration test that should fail #5950 (ParquetReadIT)
• Verify integration test passes with this change

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 61.95%. Comparing base (b6aad90) to head (4015c41).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5954      +/-   ##
==========================================
- Coverage   61.95%   61.95%   -0.01%     
==========================================
  Files         323      323              
  Lines       11727    11727              
  Branches      821      821              
==========================================
- Hits         7266     7265       -1     
- Misses       4461     4462       +1     

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