deps: [iceberg] bump Iceberg Rust to 0.8.0

[mbutrovich]

Draft as we're only testing rc1 at the moment.

Which issue does this PR close?

Closes #.

Rationale for this change

What changes are included in this PR?

How are these changes tested?

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.50%. Comparing base (f09f8af) to head (3a2f9ec).
⚠️ Report is 838 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2935      +/-   ##
============================================
+ Coverage     56.12%   59.50%   +3.37%     
- Complexity      976     1381     +405     
============================================
  Files           119      167      +48     
  Lines         11743    15524    +3781     
  Branches       2251     2575     +324     
============================================
+ Hits           6591     9237    +2646     
- Misses         4012     4989     +977     
- Partials       1140     1298     +158     

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[mbutrovich]

Closing since #3051 moves us to a newer commit.