Skip verify versions for buggy cgroup2 handling

Versions 5.1.1 to 5.3.0 of Elasticsearch had a problem where these
versions did not handle new kernels properly due to improper handling of
cgroup v2. On Linux kernels that support cgroup2 and the unified
hierarchy is mounted, Elasticsearch would never start. This means tests
on such systems where we try to start Elasticsearch will never
succeed. This commit skips these tests on OS that have the unified
cgroup v2 hierarchy.

qa/verify-version-constants/build.gradle

@@ -32,6 +32,10 @@ task bwcTest {
 }
 
 for (Version version : versionCollection.versionsIndexCompatibleWithCurrent) {
+    // the BWC version under test will fail to start in this situation so we skip creating the test task
+    if (project.cgroupsV2Enabled && version.isVersionBrokenIfCgroupsV2Enabled()) {
+        continue
+    }
     String baseName = "v${version}"
     Task oldClusterTest = tasks.create(name: "${baseName}#oldClusterTest", type: RestIntegTestTask) {
         mustRunAfter(precommit)