Enable IPv6 by default in Keycloak v22

[megian]

Context

Keycloak v22 ships with IPv6 enabled by default. Revise the component according IPv4 settings.

Alternatives

N/A. Ignoring IPv6 might cause malfunctions in the future.

[megian]

Tested with the version 22.0.5.

Before:

JAVA_OPTS already set in environment; overriding default settings with values: -XX:MaxRAMPercentage=50.0 -Djava.net.preferIPv4Stack=true -Djgroups.dns.query=keycloakx-headless
....
2024-02-22 16:11:26,990 INFO  [io.quarkus] (main) Keycloak 22.0.5 on JVM (powered by Quarkus 3.2.7.Final) started in 58.088s. Listening on: http://0.0.0.0:8080 and https://0.0.0.0:8443

After:

JAVA_OPTS already set in environment; overriding default settings with values: -XX:MaxRAMPercentage=50.0 -Djgroups.dns.query=keycloakx-headless
...
2024-02-22 16:21:45,174 INFO  [io.quarkus] (main) Keycloak 22.0.5 on JVM (powered by Quarkus 3.2.7.Final) started in 56.783s. Listening on: http://0.0.0.0:8080 and https://0.0.0.0:8443

Actually equal.

As Keycloak >= v22 is listening on IPv4 and IPv6 by default. It makes sense to switch to this. If you need to prefer either IPv4 or IPv6 you can still override it.