Update actions/checkout action to v4

[juul-mobile-bot]

This PR contains the following updates:

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

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⚠ Dependency Lookup Warnings ⚠

Warnings were logged while processing this repo. Please check the logs for more information.

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Release Notes

actions/checkout (actions/checkout)

v4

Compare Source

• Support fetching without the --progress option
• Update to node20

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Configuration

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[codecov]

Codecov Report

Merging #217 (51829d9) into main (56a59f1) will increase coverage by 0.71%.
Report is 144 commits behind head on main.
The diff coverage is 45.45%.

@@             Coverage Diff              @@
##               main     #217      +/-   ##
============================================
+ Coverage     57.25%   57.97%   +0.71%     
  Complexity       11       11              
============================================
  Files             8        8              
  Lines           613      652      +39     
  Branches        145      144       -1     
============================================
+ Hits            351      378      +27     
- Misses          223      235      +12     
  Partials         39       39              

Files Changed	Coverage Δ
koap/src/commonMain/kotlin/Encoder.kt	71.69% <ø> (+3.27%)	⬆️
koap/src/commonMain/kotlin/ToFormat.kt	26.31% <ø> (ø)
koap/src/commonMain/kotlin/Debug.kt	26.08% <25.00%> (-1.19%)	⬇️
koap/src/commonMain/kotlin/Message.kt	57.85% <33.33%> (-1.38%)	⬇️
koap/src/commonMain/kotlin/ByteArrayReader.kt	68.08% <66.66%> (-0.10%)	⬇️
koap/src/commonMain/kotlin/Decoder.kt	53.74% <66.66%> (+1.62%)	⬆️
koap/src/commonMain/kotlin/Header.kt	53.84% <100.00%> (+3.84%)	⬆️

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