fix: implement report=True for RNTuple.iterate

[KaranSinghDev]

Fixes #1628

RNTuple.iterate accepted a report parameter but never used it. As a result:

• uproot.iterate("file.root:rntuple", report=True) crashed with ValueError: too many values to unpack (expected 2) at src/uproot/behaviors/TBranch.py:216.
  • rn.iterate(report=True) silently returned a bare Array instead of the (arrays, Report) tuple that the docstring promises.

I have added the regression test (tests/test_1630_rntuple_iterate_report.py), mirroring the format of the existing TTree iterate-report tests in tests/test_0043_iterate_function.py.

This PR yields (arrays, Report) when report=True, matching the TTree contract. The report=False path is unchanged.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.76%. Comparing base (fe9ad24) to head (f72a83d).

Additional details and impacted files

Files with missing lines	Coverage Δ
src/uproot/behaviors/RNTuple.py	70.98% <100.00%> (+0.22%)	⬆️