roachtest: increase timeout for hibernate test

We noticed that on s390x the hibernate test can timeout after 5 hours.
There are also several runs that succeeded but came close to timing out.
We are going to bump the timeout to give that platform more chance to
finish the test.

Fixes #153029

Release note: none

Epic: none

Author: spilchen

pkg/cmd/roachtest/tests/hibernate.go

@@ -251,7 +251,7 @@ func registerHibernate(r registry.Registry, opt hibernateOptions) {
 		NativeLibs:       registry.LibGEOS,
 		CompatibleClouds: registry.AllExceptAWS,
 		Suites:           registry.Suites(registry.Nightly, registry.ORM),
-		Timeout:          5 * time.Hour,
+		Timeout:          6 * time.Hour,
 		Run: func(ctx context.Context, t test.Test, c cluster.Cluster) {
 			runHibernate(ctx, t, c)
 		},