Fix logic to detect updated projects

[maximlt]

Fixes #439

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[github-actions]

Your changes were successfully integrated in the dev site, make sure to review
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You can also download an archive of the site from the workflow summary page which comes in handy
when your dev site built was overriden by another PR (we have a single dev site!).

[github-actions]

Your changes were successfully integrated in the dev site, make sure to review
the pages of the projects you touched before merging this PR: https://holoviz-dev.github.io/examples/.
You can also download an archive of the site from the workflow summary page which comes in handy
when your dev site built was overriden by another PR (we have a single dev site!).

[github-actions]

Your changes were successfully integrated in the dev site, make sure to review
the pages of the projects you touched before merging this PR: https://holoviz-dev.github.io/examples/.
You can also download an archive of the site from the workflow summary page which comes in handy
when your dev site built was overriden by another PR (we have a single dev site!).