Update GitHub Artifact Actions (major)

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/download-artifact	action	major	v5 -> v6
actions/upload-artifact	action	major	v4 -> v5

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Release Notes

actions/download-artifact (actions/download-artifact)

v6

Compare Source

actions/upload-artifact (actions/upload-artifact)

v5

Compare Source

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This PR was generated by Mend Renovate. View the repository job log.

[github-actions]

Job Summary for Gradle

Check PR :: kotlin-tests

Gradle Root Project	Requested Tasks	Gradle Version	Build Outcome	Build Scan®
develocity-api-kotlin	check	9.1.0	❌
dak-example-gradle-project	dependencies --configuration runtimeClasspath	9.0.0	✅
dak-example-gradle-project	run --args "buildStartTime>-10h buildTool:gradle"	9.0.0	✅
dak-example-gradle-task-main-…	userBuildPerformanceMetrics --user runner --period=-10h	9.0.0	✅
dak-example-gradle-task-main-…	:buildSrc:dependencies --configuration runtimeClasspath	9.0.0	✅
dak-example-gradle-task-build…	:generateExternalPluginSpecBuilders	9.0.0	✅