GH-45073: [C++][Parquet] Fix generation of repetition levels for encryption test data

[adamreeve]

Rationale for this change

This makes the test data readable by other Parquet implementations that validate the repetition levels.

What changes are included in this PR?

• Corrects the generation of encryption test files so that the int64 list columns correctly start lists with repetition level 0.
• Updates the parquet-testing submodule to use the corrected files (TODO)

Are these changes tested?

Yes, covered by existing tests.

Are there any user-facing changes?

No

• GitHub Issue: [C++][Parquet] Encryption test files are generated with invalid repetition levels #45073

[adamreeve]

The tests will fail until the test data is first fixed in apache/parquet-testing#65 and the submodule updated here.