fix: use Python ints for start/stop when reading a single basket

[ariostas]

xrootd refuses to work with NumPy ints, which was preventing reading single baskets with xrootd. I simply converted them to Python ints.

Closes #1582

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.42%. Comparing base (f19065d) to head (3f4dd28).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

Files with missing lines	Coverage Δ
src/uproot/behaviors/TBranch.py	83.41% <100.00%> (+0.01%)	⬆️

... and 2 files with indirect coverage changes

[ianna]

@ariostas - Excellent catch! Thanks for fixing it!