Don't show telemetry opt-in/out notice when it has been disabled via yml config.

[lukeelmers]

Partially addresses #110638

This fixes an issue where a link to opt out of telemetry was provided from the welcome screen even when telemetry.allowChangingOptInStatus was set to false in the kibana.yml. This created a confusing experience for super users, because they still had access to stack management, but were unable to access the actual setting for changing the opt in status due to the allowChangingOptInStatus disabling it.

To test:

# Should display link if logging in with super user (`elastic / changeme`)
telemetry.enabled: true
telemetry.allowChangingOptInStatus: true

# Should not display link
telemetry.enabled: true
telemetry.allowChangingOptInStatus: false

Screenshots:

Before

After (note the fine print is missing opt in/out link)

[lukeelmers]

@elasticmachine merge upstream

[elasticmachine]

Pinging @elastic/kibana-core (Team:Core)

[kibanamachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 8a82a1b
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Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
home	76.2KB	76.2KB	+47.0B

History

• 💚 Build #3000 succeeded b3a6a92

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

cc @lukeelmers

[TinaHeiligers]

Changes LGTM.

[kibanamachine]

💚 Backport successful

Status	Branch	Result
✅	8.0
✅	7.16
✅	7.15

The backport PRs will be merged automatically after passing CI.