refactor(rust): Allow polars to pass cargo check on windows

[squnit]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 2 lines in your changes missing coverage. Please review.

Project coverage is 79.86%. Comparing base (4dc90a9) to head (ef37f90).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-utils/src/mem.rs	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #18498      +/-   ##
==========================================
- Coverage   79.87%   79.86%   -0.02%     
==========================================
  Files        1501     1501              
  Lines      202032   202032              
  Branches     2868     2868              
==========================================
- Hits       161370   161346      -24     
- Misses      40115    40139      +24     
  Partials      547      547              

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[squnit]

Relevant logs before this commit when run on windows

warning: unused variable: `slice`
  --> crates\polars-utils\src\mem.rs:57:27
   |
57 | pub fn madvise_sequential(slice: &[u8]) {
   |                           ^^^^^ help: if this is intentional, prefix it with an underscore: `_slice`
   |
   = note: `#[warn(unused_variables)]` on by default

warning: unused variable: `slice`
  --> crates\polars-utils\src\mem.rs:63:25
   |
63 | pub fn madvise_willneed(slice: &[u8]) {
   |                         ^^^^^ help: if this is intentional, prefix it with an underscore: `_slice`

warning: `polars-utils` (lib) generated 2 warnings

warning: unused import: `std::collections::btree_map::Entry`
 --> crates\polars-io\src\mmap.rs:1:5
  |
1 | use std::collections::btree_map::Entry;
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

warning: unused import: `std::collections::BTreeMap`
 --> crates\polars-io\src\mmap.rs:2:5
  |
2 | use std::collections::BTreeMap;
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^

warning: unused import: `Mutex`
 --> crates\polars-io\src\mmap.rs:5:22
  |
5 | use std::sync::{Arc, Mutex};
  |                      ^^^^^

warning: unused import: `once_cell::sync::Lazy`
 --> crates\polars-io\src\mmap.rs:8:5
  |
8 | use once_cell::sync::Lazy;
  |     ^^^^^^^^^^^^^^^^^^^^^

warning: unused import: `polars_bail`
  --> crates\polars-io\src\mmap.rs:10:20
   |
10 | use polars_error::{polars_bail, PolarsResult};
   |                    ^^^^^^^^^^^

warning: unused variable: `file`
  --> crates\polars-io\src\mmap.rs:63:26
   |
63 | pub fn ensure_not_mapped(file: &File) -> PolarsResult<()> {
   |                          ^^^^ help: if this is intentional, prefix it with an underscore: `_file`
   |
   = note: `#[warn(unused_variables)]` on by default

warning: `polars-io` (lib) generated 6 warnings (run `cargo fix --lib -p polars-io` to apply 5 suggestions)

warning: unused import: `self`
 --> crates\polars-python\src\file.rs:2:15
  |
2 | use std::fs::{self, File};
  |               ^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

warning: `polars-python` (lib) generated 1 warning (run `cargo fix --lib -p polars-python` to apply 1 suggestion)

[ritchie46]

LGTM. Thanks!