chore: [release-3.0.x] feat: Added Interactive Sandbox to Quickstart tutorial

[grafanabot]

Backport 97212ea from #12701

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What this PR does / why we need it:

This adds a link to an interactive sandbox of the quick-start demo. This demo can be run online via the Killercoda platform so users do not need to meet the prerequisites for installation if they don't want to.

Which issue(s) this PR fixes:
NA

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
• Changes that require user attention or interaction to upgrade are documented in docs/sources/setup/upgrade/_index.md
• For Helm chart changes bump the Helm chart version in production/helm/loki/Chart.yaml and update production/helm/loki/CHANGELOG.md and production/helm/loki/README.md. Example PR
• If the change is deprecating or removing a configuration option, update the deprecated-config.yaml and deleted-config.yaml files respectively in the tools/deprecated-config-checker directory. Example PR