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

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

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Configuration

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PR-Codex overview

This PR updates the GitHub Actions versions and distributions for the workflows in the .github/workflows directory.

Detailed summary

• Updated the version of actions/checkout to 3df4ab11eba7bda6032a0b82a6bb43b11571feac (v4) in multiple workflows.
• Updated the version of actions/setup-java to v3 and set the distribution to temurin in the mvn.yml and codecov.yml workflows.

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[yegor256]

@rultor please, try to merge, since 8 checks have passed

[rultor]

@rultor please, try to merge, since 8 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 8 checks have passed

@yegor256 Done! FYI, the full log is here (took me 31min)