Also fixes links to new section and refactors some existing content
for the GitLab 12.2 changes.

Fix pipelines not always being created after a push

Closes #66196

See merge request gitlab-org/gitlab-ce!31927

Update docs jira service page screenshot

Closes #64778

See merge request gitlab-org/gitlab-ce!31911

Update doc/user/project/integrations/jira.md, doc/user/project/integrations/img/jira_service_page_v12_2.png files
Deleted doc/user/project/integrations/img/jira_service_page.png

Escape vertical bars inside code blocks in quick_actions.md

See merge request gitlab-org/gitlab-ce!31556

Escape vertical bars inside code blocks in quick_actions.md - Markdown parsing in previews and Gitlab.com appear to parse these as table delimiters even when inside a code block.

Update screenshot to fix bad html

Closes #63920

See merge request gitlab-org/gitlab-ce!31889

Fix required runner permissions

Closes #52513

See merge request gitlab-org/gitlab-ce!31598

Docs: Improve clarity of SCIM workflow

Closes #65097

See merge request gitlab-org/gitlab-ce!31881

Quarantine failing test

See merge request gitlab-org/gitlab-ce!31943

Improve docs for cross-project MR dependencies

Closes gitlab-ee#12980

See merge request gitlab-org/gitlab-ce!31904

Addressing a documentation review by Marcia!

Docs: Refresh CI quick start screenshots

See merge request gitlab-org/gitlab-ce!31877

Remove MySQL references from development docs

See merge request gitlab-org/gitlab-ce!31712

Mentions `auth.log` on Rate limit docs

See merge request gitlab-org/gitlab-ce!31906

Requests over the rate limit are logged into `auth.log`

Update srmX configuration description

See merge request gitlab-org/gitlab-ce!31142

add GitLab CI job token API authentication section

See merge request gitlab-org/gitlab-ce!30698

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/31741 introduced
a regression where not all the right parameters would be passed into
`Ci::CreatePipelineService`. We fix this by breaking out the pipeline
parameters and reusing a method from `Gitlab::DataBuilder::Push`.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/66196

Merge branch '50020-fe-allow-email-notifications-to-be-disabled-for-all-users-of-a-group' into 'master'

UI for disabling group/project email notifications

Closes #50020

See merge request gitlab-org/gitlab-ce!30961

- Adds UI to configure in group and project settings
- Removes notification configuration for users when
disabled at group or project level

Migrate legacy uploads rake tasks

See merge request gitlab-org/gitlab-ce!29409

Add new table to store email domain per group

See merge request gitlab-org/gitlab-ce!31071

In order to save user preferences regarding
user emails allowed to be invited to group

Add foreign_key and down method

Change adding foreign key

Add partial call to view

Add changelog entry

Fix schema

Embed specific metrics chart in issue

Closes #62971

See merge request gitlab-org/gitlab-ce!31644

This MR adds the styles for displaying a single
chart next to another one when embedding them
in an issue.

Fix starrers counts after searching

See merge request gitlab-org/gitlab-ce!31823

Look up upstream commits once before queuing ProcessCommitWorkers

Closes #65464

See merge request gitlab-org/gitlab-ce!31871

Optimize DB indexes for ES indexing of notes

See merge request gitlab-org/gitlab-ce!31846

Expire project caches once per push instead of once per ref

Closes #52046

See merge request gitlab-org/gitlab-ce!31876

Previously `ProjectCacheWorker` would be scheduled once per ref, which
would generate unnecessary I/O and load on Sidekiq, especially if many
tags or branches were pushed at once. `ProjectCacheWorker` would expire
three items:

1. Repository size: This only needs to be updated once per push.
2. Commit count: This only needs to be updated if the default branch
   is updated.
3. Project method caches: This only needs to be updated if the default
   branch changes, but only if certain files change (e.g. README,
   CHANGELOG, etc.).

Because the third item requires looking at the actual changes in the
commit deltas, we schedule one `ProjectCacheWorker` to handle the first
two cases, and schedule a separate `ProjectCacheWorker` for the third
case if it is needed. As a result, this brings down the number of
`ProjectCacheWorker` jobs from N to 2.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/52046

Fix Arel deprecation warning in clusters_hierarchy

See merge request gitlab-org/gitlab-ce!31916

To index notes, we exclude system notes and use `find_in_batches` to
load them in batches for submission to the ES bulk import API.
These queries often result in DB timeouts because the usage of
`ORDER BY id` results in the `notes_pkey` index being used.

This adds an optimized partial index, and removes the unused index
`index_notes_on_noteable_type` which is already covered for our
usage by the existing `index_notes_on_noteable_id_and_noteable_type`.

Newer versions of PostgreSQL (at least 11) are smarter about this and
use `index_notes_on_project_id_and_noteable_type` instead, so we might
be able to remove the partial index again in the future.

Instead of checking if a commit already exists in the upstream project
in its ProcessCommitWorker and bailing out if it does, we check the
existence of all commits in bulk in Git::BranchHooksService, so that we
can skip scheduling ProcessCommitWorker jobs for those commits
that already exist upstream entirely.

Remove Security Dashboard feature flag

See merge request gitlab-org/gitlab-ce!31820