chore(deps): update actions/checkout action to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v3 -> v4

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Release Notes

actions/checkout (actions/checkout)

v4

Compare Source

• Check out other refs/* by commit if provided, fall back to ref by @​orhantoy in https://github.com/actions/checkout/pull/1924

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Configuration

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[codecov]

Codecov Report

Merging #80 (3c63467) into main (de7bbdb) will increase coverage by 0.12%.
Report is 21 commits behind head on main.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #80      +/-   ##
==========================================
+ Coverage   96.10%   96.23%   +0.12%     
==========================================
  Files          22       14       -8     
  Lines        1079      717     -362     
==========================================
- Hits         1037      690     -347     
+ Misses         42       27      -15     

Files	Coverage Δ
algoworld_contracts/swapper/asa_to_asa_swapper.py	100.00% <ø> (ø)
...lgoworld_contracts/swapper/asas_to_algo_swapper.py	100.00% <ø> (ø)
algoworld_contracts/swapper/swap_proxy.py	100.00% <ø> (ø)
tests/helpers/constants.py	100.00% <100.00%> (ø)
tests/helpers/utils.py	87.96% <ø> (ø)
tests/swapper/test_asa_to_asa_swapper.py	100.00% <ø> (ø)
tests/swapper/test_asas_to_algo_swapper.py	99.19% <ø> (ø)

... and 1 file with indirect coverage changes

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