rust-toolchain: Update

[rse-ci-imperial]

Automatic change by the update-rust-toolchain Github Action.

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[codecov]

Codecov Report

❌ Patch coverage is 45.45455% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.44%. Comparing base (d588b76) to head (4d619e9).
⚠️ Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
src/asset.rs	0.00%	3 Missing ⚠️
src/simulation/investment.rs	33.33%	2 Missing ⚠️
src/input/process/availability.rs	0.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1410      +/-   ##
==========================================
+ Coverage   89.42%   89.44%   +0.02%     
==========================================
  Files          59       59              
  Lines        8367     8364       -3     
  Branches     8367     8364       -3     
==========================================
- Hits         7482     7481       -1     
+ Misses        564      562       -2     
  Partials      321      321              

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