Fix schema parsing fallthrough

[Chaho12]

Description

Fixes bug where there is fallthrough when parsing schema

You can test via

SHOW CREATE SCHEMA information_schema
SHOW TABLES IN {db}

Additional context and related issues

Error log

java.lang.IndexOutOfBoundsException: index (1) must be less than size (1)
	at com.google.common.base.Preconditions.checkElementIndex(Preconditions.java:1372)
	at com.google.common.base.Preconditions.checkElementIndex(Preconditions.java:1354)
	at com.google.common.collect.SingletonImmutableList.get(SingletonImmutableList.java:46)
	at io.trino.gateway.ha.router.TrinoQueryProperties.setCatalogAndSchemaNameFromSchemaQualifiedName(TrinoQueryProperties.java:380)
	at io.trino.gateway.ha.router.TrinoQueryProperties.getNames(TrinoQueryProperties.java:340)
	at io.trino.gateway.ha.router.TrinoQueryProperties.processRequestBody(TrinoQueryProperties.java:201)
	at io.trino.gateway.ha.router.TrinoQueryProperties.<init>(TrinoQueryProperties.java:144)
	at io.trino.gateway.ha.router.ExternalRoutingGroupSelector.createRequestBody(ExternalRoutingGroupSelector.java:130)
	at io.trino.gateway.ha.router.ExternalRoutingGroupSelector.findRoutingGroup(ExternalRoutingGroupSelector.java:96)
	at io.trino.gateway.ha.handler.RoutingTargetHandler.getBackendFromRoutingGroup(RoutingTargetHandler.java:86)
	at io.trino.gateway.ha.handler.RoutingTargetHandler.lambda$getRoutingDestination$0(RoutingTargetHandler.java:66)
	at java.base/java.util.Optional.orElseGet(Optional.java:364)
	at io.trino.gateway.ha.handler.RoutingTargetHandler.getRoutingDestination(RoutingTargetHandler.java:66)
	at io.trino.gateway.proxyserver.RouteToBackendResource.postHandler(RouteToBackendResource.java:67)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
	at java.base/java.lang.reflect.Method.invoke(Method.java:580)
	at org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory.lambda$static$0(ResourceMethodInvocationHandlerFactory.java:52)
	at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher$1.run(AbstractJavaResourceMethodDispatcher.java:146)
	at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:189)
	at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$VoidOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:159)
	at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:93)
	at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:478)
	at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:400)
	at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:81)
	at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:274)
	at org.glassfish.jersey.internal.Errors$1.call(Errors.java:248)
	at org.glassfish.jersey.internal.Errors$1.call(Errors.java:244)

Release notes

(x) This is not user-visible or is docs only, and no release notes are required.
( ) Release notes are required, with the following suggested text:

* Fix some things.