Fix postgres image version

[maswin]

Description

Recently trino gateway build steps have started to fail - https://github.com/trinodb/trino-gateway/actions/runs/16999454601/job/48197983562

Trinogateway always pulls latest postgres image which might result in unexpected failures. Its better to pin to a version

Release notes

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[oneonestar]

We are currently using postgres:16 in multiple places.
To ensure consistency, we should standardize on a single version.
Please either upgrade everything to 17 or align this with 16.

trino-gateway/gateway-ha/src/test/java/io/trino/gateway/TrinoGatewayRunner.java

Line 46 in e521a3f

PostgreSQLContainer<?> postgres = new PostgreSQLContainer("postgres:16");

[maswin]

We are currently using postgres:16 in multiple places. To ensure consistency, we should standardize on a single version. Please either upgrade everything to 17 or align this with 16.

trino-gateway/gateway-ha/src/test/java/io/trino/gateway/TrinoGatewayRunner.java

Line 46 in e521a3f

PostgreSQLContainer<?> postgres = new PostgreSQLContainer("postgres:16");

Aligned this version to 16

[ebyhr]

CI is still failing though the version pin itself is a good idea.
https://github.com/trinodb/trino-gateway/actions/runs/17046970320/job/48325182279?pr=753

.