Update actions/checkout action to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v4 → v6

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Release Notes

actions/checkout (actions/checkout)

v6

Compare Source

v5

Compare Source

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• If you want to rebase/retry this PR, check this box

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

[yegor256]

@rultor please, try to merge, since 1 checks have passed

[rultor]

@rultor please, try to merge, since 1 checks have passed

@yegor256 OK, I'll try to merge now. You can check the progress of the merge here.

[rultor]

@rultor please, try to merge, since 1 checks have passed

@renovate[bot] @yegor256 Oops, I failed. You can see the full log here (spent 8s).

++ dirname ./run.sh
+ cd .
+ echo 2511
+ echo '2.0-SNAPSHOT BUILD'
2.0-SNAPSHOT BUILD
+ date
Fri Nov 21 03:02:33 UTC 2025
+ uptime
 03:02:33 up 5 min,  0 users,  load average: 2.03, 0.47, 0.15
+ cat
com.rultor.spi.Profile: There is no 'merge' section in .rultor.yml for branch master in repo yegor256/hangman
	at com.rultor.agents.req.StartsRequest.docker(StartsRequest.java:297)
	at com.rultor.agents.req.StartsRequest.vars(StartsRequest.java:202)
	at com.rultor.agents.req.StartsRequest.script(StartsRequest.java:108)
	at com.rultor.agents.req.StartsRequest.process(StartsRequest.java:69)
	at com.rultor.agents.AbstractAgent.execute(AbstractAgent.java:48)
	at com.rultor.spi.Agent.execute(Agent.java:65)
	at com.rultor.agents.VerboseAgent.execute(VerboseAgent.java:35)
	at com.rultor.Routine.process(Routine.java:178)
	at com.rultor.Routine.unsafe_aroundBody0(Routine.java:155)
	at com.rultor.Routine.run(Routine.java:1)
	at org.aspectj.runtime.reflect.JoinPointImpl.proceed(JoinPointImpl.java:164)
	at com.jcabi.aspects.aj.MethodInterrupter.wrap(MethodInterrupter.java:109)
	at com.rultor.Routine.unsafe(Routine.java:150)
	at com.rultor.Routine.run(Routine.java:115)
	at com.jcabi.log.VerboseRunnable.run(VerboseRunnable.java:190)
	at com.jcabi.aspects.aj.MethodScheduler.lambda./run.sh(MethodScheduler.java:194)
	at java.base/java.util.concurrent.Executors.call(Executors.java:572)
	at java.base/java.util.concurrent.FutureTask.runAndReset(FutureTask.java:358)
	at java.base/java.util.concurrent.ScheduledThreadPoolExecutor.run(ScheduledThreadPoolExecutor.java:305)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
	at java.base/java.util.concurrent.ThreadPoolExecutor.run(ThreadPoolExecutor.java:642)
	at com.jcabi.log.VerboseThreads.run(VerboseThreads.java:222)
	at java.base/java.lang.Thread.run(Thread.java:1583)

+ exit -1
'cid' file is absent, most probably the Docker container wasn't started correctly