Dashboard validation error shows up in Issue view and cluster health views

Summary

When visiting an issue page that had a dashboard link in a comment, the dashboard validation error appears at the top of the page.

Also, the warning shows up in the Cluster Health view.

Issue view	Cluster Health View
Example link	Example link

This is because the warnings graphQL endpoint gets called even in these places. The endpoint should be called only on the Operation > Metrics page.

Steps to reproduce

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Example Project

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What is the current bug behavior?

(What actually happens)

What is the expected correct behavior?

(What you should see instead)

Relevant logs and/or screenshots

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Output of checks

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Results of GitLab environment info

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`sudo gitlab-rake gitlab:env:info`)

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`sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production`)

Results of GitLab application Check

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sudo gitlab-rake gitlab:check SANITIZE=true)
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sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true)
(we will only investigate if the tests are passing)

Possible fixes

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