Bump taskcluster from 20.0.0 to 21.0.0

[dependabot-preview]

Bumps taskcluster from 20.0.0 to 21.0.0.

Release notes

Sourced from taskcluster's releases.

v21.0.0

[MAJOR] (bug 1578900) * Worker Manager AWS Provider now requires the ec2:DescribeRegions permission in addition to the previous permissions.
The full permissions set is documented in the deploying workers section of the manual.

• Worker Manager AWS Provider now uses all the configs from the array of launchConfigs worker pools use, rather than a
  single, randomly selected config. This allows per-region and per-zone resources to be specified. MinCapacity and
  MaxCapacity are now specified for the whole worker pool as opposed to for every individual config.

some/worker:
  config:
    minCapacity: 25
    maxCapacity: 50
-   regions: [us-central1, ...]
-   capacityPerInstance: 1
-   ...
+   launchConfigs:
+     - region: us-central1
+       capacityPerInstance: 1
+       ...

[minor] (#1576) AWS Provisioner support has been removed from the UI and it is no longer a navigation menu item.
This service has not been a part of the Taskcluster deployment for some time.

(bug 1589403) Fix a regression in Github logins. A header was not being set.

(#1573) The UI now properly listens to pulse messages.
It was previously hard-coded to a value that would only
work on https://taskcluster-ui.herokuapp.com/.
We now read the pulse namespace from PULSE_USERNAME.

(#1665) The web-server service now properly configures CORS for
its third party login endpoints /login/oauth/token and
/login/oauth/credentials.

(bug 1589368) Taskcluster-GitHub now correctly reports InsufficientScopes errors, instead of "Cannot read property 'unsatisfied' of undefined".

Changelog

Sourced from taskcluster's changelog.

v21.0.0

[MAJOR] (bug 1578900) * Worker Manager AWS Provider now requires the ec2:DescribeRegions permission in addition to the previous permissions.
The full permissions set is documented in the deploying workers section of the manual.

• Worker Manager AWS Provider now uses all the configs from the array of launchConfigs worker pools use, rather than a
  single, randomly selected config. This allows per-region and per-zone resources to be specified. MinCapacity and
  MaxCapacity are now specified for the whole worker pool as opposed to for every individual config.

some/worker:
  config:
    minCapacity: 25
    maxCapacity: 50
-   regions: [us-central1, ...]
-   capacityPerInstance: 1
-   ...
+   launchConfigs:
+     - region: us-central1
+       capacityPerInstance: 1
+       ...

[minor] (#1576) AWS Provisioner support has been removed from the UI and it is no longer a navigation menu item.
This service has not been a part of the Taskcluster deployment for some time.

(bug 1589403) Fix a regression in Github logins. A header was not being set.

(#1573) The UI now properly listens to pulse messages.
It was previously hard-coded to a value that would only
work on https://taskcluster-ui.herokuapp.com/.
We now read the pulse namespace from PULSE_USERNAME.

(#1665) The web-server service now properly configures CORS for
its third party login endpoints /login/oauth/token and
/login/oauth/credentials.

(bug 1589368) Taskcluster-GitHub now correctly reports InsufficientScopes errors, instead of "Cannot read property 'unsatisfied' of undefined".

Commits

• 0d0d594 v21.0.0
• 0b0ab23 Merge pull request #1674 from djmitche/bug1589368
• 1fb19d9 Bug 1587901 unhandled rejection in notify tests (#1667)
• a1b8c89 Add docs and changelog for bug 1578900 (#1677)
• 3569807 Fix aws provider workerconfig (#1678)
• a19231a Fix aws provider workerconfig
• 32d64e2 Add docs and changelog for bug 1578900
• e34eaaf Merge pull request #1559 from Jo-IE/uncouple-data-from-ui
• fec8067 Merge pull request #1666 from helfi92/third-party-login-cors
• 430de7f Fix tests
• Additional commits viewable in compare view

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