Fix error 500 renaming group. Also added specs and changelog.

Closes #17922 and #23223

See merge request !8201

Prevent erasing Milestone filter when updating other filters

Closes #25561

See merge request !8117

Fix copy in Issue Tracker empty state

See merge request !8202

Inject ::UploadedFile from Multipart middleware

Closes #25888

See merge request !8215

Adds CSS class to status icon on MR widget to prevent non-colored icon

Closes #25898

See merge request !8219

Setup teaspoon tests for Issuable

Rename groups with .git in the end of the path

Closes #25862

See merge request !8199

Allow projects with dashboard as path

See merge request !8216

I mistakenly concluded Rack::Multipart injects File instances into the
params. These should be UploadedFile instances. This reuses a mock
UploadedFile class we already had in GitLab.

Added support for Authentiq OAuth provider

See merge request !8038

Ensure nil User-Agent doesn't break the CI API

Closes #25895

See merge request !8213

Adds MR id to changelor

added lighter count badge background-color for on white backgrounds

See merge request !7873

Fix Import/Export labels error

Closes #24257

See merge request !8212

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Rémy Coutable <remy@rymai.me>

# Conflicts:
#   app/assets/stylesheets/pages/pipelines.scss

Homogenize revert and cherry-pick button styles generated by commits_helper.rb

Closes #25225

See merge request !8053

Account for newlines in commit messages on network graph

Closes #25681 and #21086

See merge request !8131

Display error code for U2F errors

See merge request !7305

Apply margin on alert banners only when there is one or more alerts

## What does this MR do?

Fixes extra margin added to all pages by !8151

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

## Screenshots (if relevant)

![screenshot](https://gitlab.com/gitlab-org/gitlab-ce/uploads/f8804454e82a61246d10fa026605fbb3/Screen_Shot_2016-12-19_at_2.04.42_PM.png)

## Does this MR meet the acceptance criteria?

- [ ] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #25835

See merge request !8209

Rename SlackNotificationService back to SlackService

## What does this MR do?

See https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/8191#note_20310845

## What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/25843

/cc @yorickpeterse @stanhu @smcgivern @felipe_artur @ayufan

See merge request !8208