Moved coverage reporting to cargo-llvm-cov

[jorgecarleitao]

I have been having a blast with cargo-llvm-cov by @taiki-e, https://github.com/taiki-e/cargo-llvm-cov. I observe less false positives.

This PR experiments it in this project's CI.

[codecov]

Codecov Report

Merging #1028 (2b9d376) into main (62f5892) will increase coverage by 8.91%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1028      +/-   ##
==========================================
+ Coverage   72.36%   81.27%   +8.91%     
==========================================
  Files         359      360       +1     
  Lines       19926    34309   +14383     
==========================================
+ Hits        14419    27886   +13467     
- Misses       5507     6423     +916     

Impacted Files	Coverage Δ
src/compute/aggregate/simd/native.rs	75.00% <0.00%> (-25.00%)	⬇️
src/compute/bitwise.rs	58.13% <0.00%> (-16.87%)	⬇️
src/compute/arithmetics/basic/mod.rs	33.33% <0.00%> (-16.67%)	⬇️
src/compute/arithmetics/mod.rs	59.52% <0.00%> (-10.29%)	⬇️
src/io/parquet/read/statistics/struct_.rs	54.05% <0.00%> (-7.06%)	⬇️
src/io/parquet/read/statistics/list.rs	48.97% <0.00%> (-6.20%)	⬇️
src/array/dictionary/ffi.rs	69.56% <0.00%> (-5.44%)	⬇️
src/compute/arithmetics/basic/add.rs	84.15% <0.00%> (-5.21%)	⬇️
src/compute/arithmetics/basic/mul.rs	84.15% <0.00%> (-5.21%)	⬇️
src/compute/arithmetics/basic/sub.rs	84.15% <0.00%> (-5.21%)	⬇️
... and 356 more

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