Deploy boards backend

Closes #1589

See merge request !1278

Custom empty exception class cop

See merge request !1328

Add note about how to use or escape variables inside other variables

See merge request !1324

[ci skip]

[ci skip]

Restructure Pages docs index and getting started guides

See merge request !1329

Use rollout_status_path provided in environment to fetch the data instead of hardcoded endpoint

See merge request !1323

[ci skip]

From the Ruby style guide:

    # bad
    class FooError < StandardError
    end

    # okish
    class FooError < StandardError; end

    # good
    FooError = Class.new(StandardError)

This cop does that, but only for error classes (classes where the
superclass ends in 'Error'). We have empty controllers and models, which
are perfectly valid empty classes.

Add internal endpoint to notify post-receive to Gitaly

See merge request !1254

Move all Pages related content to a single location

See merge request !1321

Port of 27354-navigation-new-button to EE

See merge request !1287

[ci skip]

[ci skip]

# Conflicts:
#	CHANGELOG.md

Merge branch '28769-raise-custom-exception-in-all-methods-of-mergeservice-that-want-to-inform-the-user-ee' into 'master'

Use exceptions for MergeService error handling

See merge request !1320

If any method called by `MergeService#execute` raises a `MergeError`,
that error's message will be logged, the model will be updated, and the
merge will fail.

CE upstream

Closes omnibus-gitlab#1361

See merge request !1319

Fix migration without DOWNTIME clause specified

See merge request !9571

Make RuboCop happy

See merge request !9554

Add button to create issue for failing build

Closes #25920

See merge request !9391

Fix inline comment images by removing wrapper #20890

Closes #20890

See merge request !5804

Fix broken dev environment in master

See merge request !9557

Keep consistent in handling indexOf results

Closes #28723

See merge request !9531

Add development fixtures for nested groups

See merge request !9553

Replace setInterval with setTimeout to prevent highly frequent requests

Closes #28212

See merge request !9271

[ci skip]

Fix #27840 - Improve the search bar experience on mobile

Closes #27840

See merge request !9280

[ci skip]