Disable e2e_om_ops_manager_queryable_backup in OM8 e2e variant (#466)

This pull request introduces a temporary workaround in the
`.evergreen.yml` configuration to address an issue with the queryable
backup task in OM8. A new task group is added that excludes the
problematic task, and the build variant is updated to use this new group
until the issue is resolved in: https://jira.mongodb.org/browse/CLOUDP-346008.

Author: m1kola

.evergreen.yml

@@ -1110,6 +1110,17 @@ task_groups:
       - e2e_om_ops_manager_backup
     <<: *teardown_group
 
+  # TODO (CLOUDP-346008): Remove this task group once the issue with queryable backup task is resolved in OM8
+  - name: e2e_ops_manager_kind_5_0_only_task_group_without_queryable_backup
+    max_hosts: -1
+    <<: *setup_group
+    <<: *setup_and_teardown_task
+    tasks:
+      - e2e_om_remotemode
+      - e2e_om_ops_manager_backup_restore
+      - e2e_om_ops_manager_backup
+    <<: *teardown_group
+
   # Tests features only supported on OM60
   - name: e2e_ops_manager_kind_6_0_only_task_group
     max_hosts: -1
@@ -1325,7 +1336,8 @@ buildvariants:
     <<: *base_om8_dependency
     tasks:
       - name: e2e_ops_manager_kind_only_task_group
-      - name: e2e_ops_manager_kind_5_0_only_task_group
+      # TODO (CLOUDP-346008): Replace this task group with e2e_ops_manager_kind_5_0_only_task_group once the issue with queryable backup task is resolved in OM8
+      - name: e2e_ops_manager_kind_5_0_only_task_group_without_queryable_backup
       - name: e2e_ops_manager_kind_6_0_only_task_group
       - name: e2e_ops_manager_upgrade_only_task_group