Enhance 'path' property description and requirements

[s4kh]

What this PR does / why we need it:

plugin.json routes[].path should be defined, otherwise it won't be proxied. Updated the description for the 'path' property to include a warning about empty strings and marked it as required.

Which issue(s) this PR fixes:

Fixes https://github.com/grafana/grafana-community-team/issues/715

Special notes for your reviewer:

[github-actions]

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[Copilot]

Pull request overview

This PR updates the documentation for the path property in routes[] configuration for data source plugins to clarify that it cannot be an empty string and marks it as required.

Changes:

• Updated the path property description to include a warning that it cannot be an empty string
• Marked the path property as required in the routes configuration table

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[hugohaggmark]

Hi @s4kh , this file is autogenerated from https://github.com/grafana/grafana/blob/main/docs/sources/developers/plugins/plugin.schema.json so you need to add the comment there first and then run npm -w website run prebuild in the root of this branch and it should update this file automatically

[hugohaggmark]

Opened this PR so this shouldn't happen again: #2396

[s4kh]

@hugohaggmark ran npm -w website run prebuild

[hugohaggmark]

No changes you can close this PR @s4kh 🙌