chore(deps): update docker/build-push-action action to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
docker/build-push-action	action	major	v5 -> v6

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Release Notes

docker/build-push-action (docker/build-push-action)

v6

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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[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[renovate]

Renovate Ignore Notification

Because you closed this PR without merging, Renovate will ignore this update. You will not get PRs for any future 6.x releases. But if you manually upgrade to 6.x then Renovate will re-enable minor and patch updates automatically.

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