Update kotlin to v1.9.20

[juul-mobile-bot]

This PR contains the following updates:

Package	Type	Update	Change
org.jetbrains.kotlin.plugin.serialization	plugin	patch	1.9.10 -> 1.9.20
org.jetbrains.kotlin.multiplatform	plugin	patch	1.9.10 -> 1.9.20
org.jetbrains.kotlin.js	plugin	patch	1.9.10 -> 1.9.20

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Warning

Some dependencies could not be looked up. Check the warning logs for more information.

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This PR has been generated by Renovate Bot.

[codecov]

Codecov Report

Merging #224 (80f1345) into main (56a59f1) will increase coverage by 0.71%.
Report is 151 commits behind head on main.
The diff coverage is 45.45%.

❗ Current head 80f1345 differs from pull request most recent head 22c8768. Consider uploading reports for the commit 22c8768 to get more accurate results

@@             Coverage Diff              @@
##               main     #224      +/-   ##
============================================
+ 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	Coverage Δ
koap/src/commonMain/kotlin/Encoder.kt	71.69% <ø> (+3.27%)	⬆️
koap/src/commonMain/kotlin/Header.kt	53.84% <100.00%> (+3.84%)	⬆️
koap/src/commonMain/kotlin/ToFormat.kt	26.31% <ø> (ø)
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/Debug.kt	26.08% <25.00%> (-1.19%)	⬇️
koap/src/commonMain/kotlin/Message.kt	57.85% <33.33%> (-1.38%)	⬇️