Revert MattermostNotificationService and SlackNotificationService to MattermostService and SlackService

UX Guide: split state and action guidance for color

See merge request !8204

UX Guide: add moving transition animation guidance

See merge request !8147

Remove "up-for-grabs" label from PROCESS.md

See merge request !8341

Set SIDEKIQ_LOG_ARGUMENTS in gitlab.rb

See merge request !8340

Fix grammar error in text about mentioned issues

See merge request !8337

Fix a Grape deprecation, use `#request_method` instead of `#route_method`

See merge request !8297

[ci skip]

Update vmstat to version 2.3.0

Closes #26114

See merge request !8318

Resolve "Clicking markdown 'Preview' tab spawns two XHR requests"

Closes #25364

See merge request !8031

Revert "Merge branch 'increase-left-padding-of-filter-row-labels' into 'master'"

See merge request !8331

This reverts merge request !8258

Go to a project order

Closes #18786

See merge request !7737

Only limit container width on issues & MRs within fixed-width container

Closes #25907

See merge request !8330

Changed the label font size

See merge request !8274

Issues/8081

See merge request !7908

Truncate the tag description and improve mobile layout for individual tag

Closes #1659

See merge request !8220

[ci skip]

Rename projects with reserved path names

See merge request !8234

Fixes issue boards list colored top border visual glitch

See merge request !7898

# Conflicts:
#   db/schema.rb

odd sizes don't mix well with windows and some linux system fonts

Fixed discussion note resolve button SVG color

See merge request !8250

Allow to add deploy keys with write-access

Closes #1376

See merge request !7383

Rename users with namespace ending with .git

See merge request !8309