rust: upgrade to 1.75.0

[Desiki-high]

Relevant Issue (if applicable)

If there are Issues related to this PullRequest, please list it.

Details

1. reduce the binary size.
2. use more rust-clippy lints.

Types of changes

What types of changes does your PullRequest introduce? Put an x in all the boxes that apply:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation Update (if none of the other choices apply)

Checklist

Go over all the following points, and put an x in all the boxes that apply.

• I have updated the documentation accordingly.
• I have added tests to cover my changes.

[codecov]

Codecov Report

Attention: Patch coverage is 71.42857% with 2 lines in your changes missing coverage. Please review.

Project coverage is 60.70%. Comparing base (7c49849) to head (4368a29).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
src/bin/nydus-image/main.rs	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1634      +/-   ##
==========================================
- Coverage   61.24%   60.70%   -0.54%     
==========================================
  Files         146      146              
  Lines       48189    48355     +166     
  Branches    46156    46322     +166     
==========================================
- Hits        29513    29355     -158     
- Misses      17115    17232     +117     
- Partials     1561     1768     +207     

Files with missing lines	Coverage Δ
src/bin/nydus-image/deduplicate.rs	70.22% <100.00%> (-0.14%)	⬇️
utils/src/digest.rs	88.32% <100.00%> (ø)
src/bin/nydus-image/main.rs	0.62% <0.00%> (-0.01%)	⬇️

... and 77 files with indirect coverage changes

[imeoer]

LGTM! will retry the CI.