fix: panic unwrap on None in decoder.rs

[camilesing]

for: #5119

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Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
rust/lance-encoding/src/decoder.rs	0.00%	0 Missing and 1 partial ⚠️

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[camilesing]

@wjones127 seems CI failed because of the other PR

[wjones127]

This is the error:

error[E0499]: cannot borrow `*column_infos` as mutable more than once at a time
   --> rust/lance-encoding/src/decoder.rs:829:25
    |
792 |             let column_info = column_infos.expect_next()?;
    |                               ------------ first mutable borrow occurs here
...
829 |                         column_infos,
    |                         ^^^^^^^^^^^^ second mutable borrow occurs here
830 |                         buffers,
831 |                         &column_info,
    |                         ------------ first borrow later used here

I think you may need to call .clone().

[wjones127]

I've added the .clone() call for you and removed the unrelated changes.

[camilesing]

@wjones127 Thx you, I will pay more attention later