We do not need to link to index files, and in the future
it will be recommended to avoid it.

Update crosslinks from other docs and UI

Also updates all crosslinks including from UI code

Changelog: changed

H1 headers needs to be in YAML frontmatter now

Rename index.md to _index.md and update links
across all files.

Changelog: changed

Rename index.md to _index.md and update links
across all files.

Changelog: changed

We should not link out then back in the directory

The offering is called GitLab Self-Managed in all cases

Remove duplicated information, group similar topics together,
reorder sections and move troubleshooting to dedicated
troubleshooting page.

Update offering notes with all three offerings

This is a common source of confusion, as global variables
do not work as global keywords, but simply default variables

Refactor namespace variables default role migration to enum
Adjust default role reference from namespace to namespace_settings
Validate default pipeline variabe role on namespace settings
Restore nil allownace for the role on namespace
Move FF to namespace_settings and use no_one_allowed as default role
Fix typo in index.md
Adjust index.md docs
Restore qa tests
Leave only enum validation on namespace settings
Define DEVELOPER_ROLE in the transaction
Replace after_initialize with before_create
Move Chain Associations to 4th line
Remove restrict_user_defined_variables update to true in tests
Fallback to default if no namespace settings defined, address tests accordingly

Changelog: changed

Co-authored-by: Michael Belton <mbelton@gitlab.com>

Use "Pipeline variables" consistently and ensure the docs
cover all the cases where pipeline variables are supported.
Make it clear the risk of overriding variables and align
terminology to restricting pipeline variables to upcoming
changes.

Changelog: changed

Masked variables being replaced with `[MASKED]` or with `xxxxxxx`
depending on where the masking is happening is confusing (and currently
neither(!) are explained in the docs).

A masked variable has to be 8 characters or longer, which is exactly the
length of `[MASKED]`. We can replace the first eight `x` in each masked
variable on the Rails side with `[MASKED]` and have a slightly more
consistent outcome for users.

Co-authored-by: Marcel Amirault <mamirault@gitlab.com>

Co-authored-by: Amy Qualls <aqualls@gitlab.com>

For consistency with job naming, Update dependency name from
'build' to 'build-job1' in ci/variables doc 

Check feature flag value, pass areHiddenVariablesAvailable down
Show new "Masked and hidden" radio button
Save masked and hidden variables with masked: true, hidden: true
Load masked and hidden variables by translating booleans to options
Show "Hidden" badge if variable is hidden
Add exception: don't validate blank value when editing a hidden variable
Show different settings section text if flag is enabled
Update documentation to refer to "Visibility" instead of just "Masked"

Fix filename of scan execution policies docs page to comply with the docs standard. Filenames that consist of several words are to be joined with underscores, not hyphens. 

Find and replace across all docs to update Admin area
to **Admin** area.

Co-authored-by: Scott Hampton <shampton@gitlab.com>

Changelog: changed

Artifacts goes to PE, Variables to PA