Merge branch '50020-fe-allow-email-notifications-to-be-disabled-for-all-users-of-a-group' into 'master'

UI for disabling group/project email notifications

Closes #50020

See merge request gitlab-org/gitlab-ce!30961

(cherry picked from commit 1068483f)

7699a87e UI for disabling group/project email notification
bad143ff Rename canChangeEmailsDisabled to canDisableEmails
38b3f9ec Hide emails_disabled checkbox if disabled in group
5e1fc2f5 Apply suggestion to...
bcd5cee9 Addressed review feedback
d602fc12 Minor fixes for gitlab.pot
1ee32758 Update permissions documentation
43c87103 Vue file prettified
e5ec00ce Apply suggestion to app/views/shared/notifications/_button.html.haml
e2de0db9 Disable the subgroup checkbox
dbd7fcbd Add checked to emails_disabled group settings

Using the sed script from
https://gitlab.com/gitlab-org/gitlab-ce/issues/59758

These are not required because MySQL is not
supported anymore

- Migration updates existing groups to "owner", then sets default to
  "maintainer" so that new groups will default to that
- Update spec examples

- Migration updates existing groups to "owner", then sets default to
  "maintainer" so that new groups will default to that
- Update spec examples

Both with subgroup_creation_level set to owners and to maintainers.
Also fixed the naming of some other examples in the same spec as they
were contradicting what they were actually performing in the test.
These examples were probably copy/pasted, and not renamed.

- Change the two existing feature examples that create a subgroup to
  elucidate that the owner is creating the subgroup

- Nest two more specs inside the 'subgroup support' context detailing
  what happens when a maintainer attempts to add a subgroup (one with
  subgroup support, and one without)

- Migration updates existing groups to "owner", then sets default to
  "maintainer" so that new groups will default to that
- Update spec examples

- Migration updates existing groups to "owner", then sets default to
  "maintainer" so that new groups will default to that
- Update spec examples

Both with subgroup_creation_level set to owners and to maintainers.
Also fixed the naming of some other examples in the same spec as they
were contradicting what they were actually performing in the test.
These examples were probably copy/pasted, and not renamed.

- Change the two existing feature examples that create a subgroup to
  elucidate that the owner is creating the subgroup

- Nest two more specs inside the 'subgroup support' context detailing
  what happens when a maintainer attempts to add a subgroup (one with
  subgroup support, and one without)

- Migration updates existing groups to "owner", then sets default to
  "maintainer" so that new groups will default to that
- Update spec examples

Both with subgroup_creation_level set to owners and to maintainers.
Also fixed the naming of some other examples in the same spec as they
were contradicting what they were actually performing in the test.
These examples were probably copy/pasted, and not renamed.

- Change the two existing feature examples that create a subgroup to
  elucidate that the owner is creating the subgroup

- Nest two more specs inside the 'subgroup support' context detailing
  what happens when a maintainer attempts to add a subgroup (one with
  subgroup support, and one without)