Add missing postgres driver in getting-started

[pingtimeout]

When Polaris is built using the provided command, the docker-compose deployment cannot start given that the postgresql driver is not bundled in the Docker image. The following error can be seen during the bootstrap operation.

polaris-bootstrap-1  | Caused by: java.sql.SQLException: No suitable driver found for jdbc:postgresql://postgres:5432/POLARIS
polaris-bootstrap-1  | 	at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:708)
polaris-bootstrap-1  | 	at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:191)
polaris-bootstrap-1  | 	at org.eclipse.persistence.sessions.DefaultConnector.connect(DefaultConnector.java:102)
polaris-bootstrap-1  | 	... 40 more
polaris-bootstrap-1  | Bootstrap encountered errors during operation.
polaris-bootstrap-1  | 2025-04-24 08:29:53,602 INFO  [io.quarkus] (main) Apache Polaris Admin Tool (incubating) stopped in 0.003s

The -PeclipseLinkDeps=org.postgresql:postgresql:42.7.4 must be used at build time so that the postgres driver is included in the docker image. This commit addresses that.

[flyrain]

It was removed by #1411. After #1411, the driver should be pulled by the default build. Do we need to add it here? cc @jbonofre

[jbonofre]

I agree with @flyrain : PostgreSQL JDBC driver is now embedded by default. So, no need to add it.

[flyrain]

I think the problem would be gradle doesn't package the runtimeonly dependencies. We may add a task like this.

tasks.register('copyRuntimeLibs', Copy) {
    from configurations.runtimeClasspath
    into "$buildDir/libs/runtime"
}

[flyrain]

The postgres was added as a runtimeOnly dep: https://github.com/polaris-catalog/polaris/blob/1c684d2378e923ba410f38c1c79f12130db33f94/quarkus/server/build.gradle.kts#L52-L52

[jbonofre]

Yup, good catch. It's enough for the "distributions" (I checked on the 0.10.0-beta-incubating release, and PostgreSQL driver is included in the distribution). But probably need extra for "started guide" packages.

[pingtimeout]

Oooooh that's a nasty one. @jbonofre I can confirm that the polaris image is fine and has the postgres driver. However the polaris-admin-tool does not.

$ docker run --rm --entrypoint /bin/bash apache/polaris:postgres-latest -c "find /deployments/ -name '*.jar' | grep postgres"
/deployments/lib/main/org.postgresql.postgresql-42.7.5.jar
$ docker run --rm --entrypoint /bin/bash apache/polaris-admin-tool:postgres-latest -c "find /deployments/ -name '*.jar' | grep postgres"
$
$

[pingtimeout]

I have opened #1447 to fix the build. Closing this PR as it is not the right solution.