Either the query or query_range attribute needs to be present in the
metrics yml. The yml is invalid if both are present or neither is
present.

Validate the schema of the dashboard that is loaded by
Gitlab::MetricsDashboard::Service.

Change MetricsDashboard::Service to inherit from BaseService so that
it can reuse methods like initialize, success, error.

- Order groups by descending order of priority.
- Order panels by descending order of weight.
- Perform sorting after adding project/custom metrics.

- Add 3 functions called find_or_create_panel,
find_or_create_panel_group, and find_or_create_metric to avoid having
to use 'send'.
- Remove an unused variable.
- Freeze a constant array.

- Since each yml file can hold only one dashboard.

- Change it to the new dashboard syntax.

Create constants for IDE commit action values

See merge request gitlab-org/gitlab-ce!27613

Docs: review MR !27275

Closes #60631

See merge request gitlab-org/gitlab-ce!27585

Job artifact documentation: Added list of textual formats

Closes #56801

See merge request gitlab-org/gitlab-ce!27430

!22112 added the latest extension to this list, .log meaning
that this doc extension is valid for version >= 11.5

Closes #56801

Use Gitea logo for importer

Closes #48842

See merge request gitlab-org/gitlab-ce!27424

CE backport: "Move EE differences for app/views/projects/issues/show.html.haml"

See merge request gitlab-org/gitlab-ce!27440