Fix ADRealmTests in FIPS 140 JVMs (elastic#47437)

The changes introduced in elastic#47179 made it so that we could try to
build an SSLContext with verification mode set to None, which is
not allowed in FIPS 140 JVMs. This commit address that

Author: jkakavas

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/authc/ldap/ActiveDirectoryRealmTests.java

@@ -533,12 +533,12 @@ private Settings settings(RealmConfig.RealmIdentifier realmIdentifier, Settings
                 .put(getFullSettingKey(realmIdentifier.getName(), ActiveDirectorySessionFactorySettings.AD_DOMAIN_NAME_SETTING),
                         "ad.test.elasticsearch.com")
                 .put(getFullSettingKey(realmIdentifier, DnRoleMapperSettings.USE_UNMAPPED_GROUPS_AS_ROLES_SETTING), true);
-        if (randomBoolean()) {
+        if (inFipsJvm()) {
             builder.put(getFullSettingKey(realmIdentifier, SSLConfigurationSettings.VERIFICATION_MODE_SETTING_REALM),
                     VerificationMode.CERTIFICATE);
         } else {
             builder.put(getFullSettingKey(realmIdentifier, SSLConfigurationSettings.VERIFICATION_MODE_SETTING_REALM),
-                    VerificationMode.NONE);
+                    randomBoolean() ? VerificationMode.CERTIFICATE : VerificationMode.NONE);
         }
         return builder.put(extraSettings).build();
     }