Expand the dashboard fixture to include metrics data

What does this MR do?

This is the follow up of the MR which needed to be reverted due to a FOSS_ONLY fail

Here's my steps:

git checkout 8c2a580dbb8ab729817535e56a224216db4f73c9
export FOSS_ONLY=1 && rake frontend:fixtures && yarn jest -- spec/frontend/monitoring/components/dashboard_template_spec.js 
# fails

git checkout 9face3ed0ea62d19e306f6cfaa10a85be2a6e22f
export FOSS_ONLY=1 && rake frontend:fixtures && yarn jest -- spec/frontend/monitoring/components/dashboard_template_spec.js
# passes 

The snapshot fails once the FOSS_ONLY=1 as it differs in:

-   logspath="/monitoring/monitor-project/-/logs?environment_name=environment1"