remove csv dependency for csv-write

[ritchie46]

For feature io_csv_write we only need csv-core. So this PR removes the csv dependency under that feature flag.

[codecov]

Codecov Report

Merging #917 (8395147) into main (52b3cc5) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #917   +/-   ##
=======================================
  Coverage   71.12%   71.12%           
=======================================
  Files         346      346           
  Lines       18890    18890           
=======================================
+ Hits        13435    13436    +1     
+ Misses       5455     5454    -1     

Impacted Files	Coverage Δ
src/io/csv/mod.rs	0.00% <ø> (ø)
src/io/csv/write/mod.rs	57.77% <ø> (ø)
src/bitmap/utils/slice_iterator.rs	87.93% <0.00%> (+1.72%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 52b3cc5...8395147. Read the comment docs.