chore(camel-test-infra-postgres): upgrade postgres.container to 17.9-alpine

[github-actions]

This PR updates the postgres.container container image to version 17.9-alpine.

Update Details

• Property: postgres.container
• Image: mirror.gcr.io/postgres
• File: /home/runner/work/camel/camel/test-infra/camel-test-infra-postgres/src/main/resources/org/apache/camel/test/infra/postgres/services/container.properties
• Old version: 17.8-alpine
• New version: 17.9-alpine

Verification

Please verify:

• Container image version is compatible with existing tests
• No breaking changes in the updated version
• Tests pass with the new version

Run the following to verify:

mvn clean verify -pl camel-test-infra-postgres

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This PR was automatically created by the Container Version Upgrade workflow.