Resolve "Show the activity filter dropdown in discussion tab only, show all discussions always in changes tab"

Closes #54206

See merge request gitlab-org/gitlab-ce!24082

Resolve "Update `Milestone` sort to say say `Milestone due date`"

Closes #55369

See merge request gitlab-org/gitlab-ce!24080

Use directories.new when getting S3 directory

Closes gitlab-com/gl-infra/infrastructure#5807

See merge request gitlab-org/gitlab-ce!23981

Resolve "User activity is stuck loading when there is none"

Closes #55755

See merge request gitlab-org/gitlab-ce!24063

Upgrade GitLab QA image to Ruby 2.5

See merge request gitlab-org/gitlab-ce!24091

Remove gem install bundler from Docker-based Ruby environments

Closes #55838

See merge request gitlab-org/gitlab-ce!24093

log text_filter arg of find_element

Closes gitlab-org/quality/nightly#52

See merge request gitlab-org/gitlab-ce!24064

Discussion filters will be hidden on Commits, Pipelines, and
Changes tabs on merge requests page.

This does not affect its behavior on issues page

Updating link to correctly point to environment scope docs

See merge request gitlab-org/gitlab-ce!24023

Update mysql.md - broken link

See merge request gitlab-org/gitlab-ce!23988

Update Geo Architecture Diagram in our documentation

Closes #8592

See merge request gitlab-org/gitlab-ee!7317

Explain how to use kaniko with a registry with a custom certificate

Closes #53656

See merge request gitlab-org/gitlab-ce!23875

Fix failing EE specs in security release

See merge request gitlab/gitlab-ee!753

[master] Add a shared secret to prevent abuse of the alert endpoint

See merge request gitlab/gitlab-ee!708

[master] Adds validation to check if user can read project

See merge request gitlab/gitlabhq!2645

[master] Validate projects in MR build service

See merge request gitlab/gitlabhq!2678

[master] Project guests no longer are able to see refs page

See merge request gitlab/gitlabhq!2685

[master] SSRF - Scan Internal Ports and GCP/AWS endpoints

See merge request gitlab/gitlabhq!2689

[master] Prevent private snippet from being embeddable

See merge request gitlab/gitlabhq!2692

[master] Escape label and milestone titles to prevent XSS in GFM autocomplete

See merge request gitlab/gitlabhq!2693

[master] Guest users have access to all Job information via the API

See merge request gitlab/gitlabhq!2717

[master] SSRF in project imports with LFS

See merge request gitlab/gitlabhq!2720

[master] Group Ex-Maintainer Could maintain Access to Project's Source Code/Jobs/Pipelines/Artifacts if it had Shared Group Runner Configured

See merge request gitlab/gitlabhq!2721

bundler gem has been included in the Docker official Ruby image since 2.1.
Signed-off-by: Takuya Noguchi <takninnovationresearch@gmail.com>