Update postgres Docker tag to v18

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This PR contains the following updates:

Package	Update	Change
postgres	major	16.10 -> 18.0

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Renovate Ignore Notification

Because you closed this PR without merging, Renovate will ignore this update. You will not get PRs for any future 18.x releases. But if you manually upgrade to 18.x then Renovate will re-enable minor and patch updates automatically.

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