chore(deps): bump DataFusion dependencies to 50.2.0, refresh Cargo.lock

[mbutrovich]

Which issue does this PR close?

Closes #.

Rationale for this change

DF 50.2.0 should be a non-breaking change. Commit diff:

apache/datafusion@50.0.0...50.2.0

What changes are included in this PR?

• Bumped DF to 50.2.0
• Ran cargo update to refresh dependencies

How are these changes tested?

Ran make test-rust locally. Hopefully CI is an easy run.

[mbutrovich]

This one might be interesting to Comet:

apache/datafusion@dae0e19

I don't know how we handle avg(distinct) on decimal types now.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.14%. Comparing base (f09f8af) to head (c1c72a5).
⚠️ Report is 606 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2575      +/-   ##
============================================
+ Coverage     56.12%   59.14%   +3.02%     
- Complexity      976     1458     +482     
============================================
  Files           119      146      +27     
  Lines         11743    13659    +1916     
  Branches       2251     2357     +106     
============================================
+ Hits           6591     8079    +1488     
- Misses         4012     4357     +345     
- Partials       1140     1223      +83     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[comphead]

Thanks @mbutrovich that was a smooth upgrade