Lift template requirement for TTree Snapshot

[vepadulano]

These are the changes needed to avoid the requirement to call Snapshot to a TTree dataset with template arguments for the column types, or to JIT the call in case the template arguments are not given.

Still missing:

• Doing the same for RNTuple
• Deprecating the Snapshot call with the argument type list

[github-actions[bot]]

Test Results

    20 files      20 suites   3d 18h 36m 25s ⏱️  3 042 tests  3 041 ✅ 0 💤 1 ❌ 59 056 runs  59 055 ✅ 0 💤 1 ❌

For more details on these failures, see this check.

Results for commit f4a173d2.

:recycle: This comment has been updated with latest results.