Update nginx Docker tag to v1.31.2

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
nginx	final	minor	1.25.4 → 1.31.2
nginx	stage	minor	1.25.4 → 1.31.2
nginx	final	minor	1.25.3 → 1.31.2
nginx	stage	minor	1.25.3 → 1.31.2
nginx	final	minor	1.24.0 → 1.31.2
nginx	stage	minor	1.24.0 → 1.31.2

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