Override disabled_integrations in jh

What does this MR do and why?

Related Upstream MR to disable shimo and zentao integrations settings: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/114835

Remove the disable on shimo and zentao integrations in JH.

Full plan: https://gitlab.com/gitlab-org/gitlab/-/issues/377824#note_1317803142

Step	Upstream	JiHu	Milestone
Disable new integration settings for shimo and zentao	Add shimo and zentao to disabled integrations list https://gitlab.com/gitlab-org/gitlab/-/merge_requests/114835	Override disabled_integrations method	16.0
Delete shimo zentao db records in table integrations and zentao_tracker_data	Run migration to delete records https://gitlab.com/gitlab-org/gitlab/-/merge_requests/114721	Run the same migration and skip deleting	16.0
Remove shimo code	https://gitlab.com/gitlab-org/gitlab/-/merge_requests/114566	Move code to jh dir	16.0
Remove zentao code	https://gitlab.com/gitlab-org/gitlab/-/merge_requests/114671	Move code to jh dir	16.0

Screenshots or screen recordings

Still show the settings of shimo and zentao.

How to set up and validate locally

1. Checkout current branch
2. Mock the disabled operation from upstream
3. visit integrations settings page, path: /<group>/<project>/-/settings/integrations

diff --git a/app/models/project.rb b/app/models/project.rb
index cb218c0a49f7..63bf750ca02b 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -1664,7 +1664,7 @@ def find_or_initialize_integrations
   end
 
   def disabled_integrations
-    disabled_integrations = []
+    disabled_integrations = %w[shimo zentao]
     disabled_integrations << 'google_play' unless Feature.enabled?(:google_play_integration, self)
     disabled_integrations
   end

MR acceptance checklist

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