[C++][Parquet] Remove left over ARROW_LOG statement.

[asfimport]

Reporter: Micah Kornfield / @emkornfield
Assignee: Micah Kornfield / @emkornfield

PRs and other links:

• GitHub Pull Request #8392

_{Note: This issue was originally created as ARROW-10229. Please see the migration documentation for further details.}

[asfimport]

Antoine Pitrou / @pitrou:
Issue resolved by pull request 8392
#8392