Show link to sample folders where available

[holly-cummins]

Resolves #1010

We show a samples link if one is available. We special-case Camel and look for a suitably-named sample in the camel samples repository. We also special-case Quarkus and look in the quickstarts repository.

For example,

• https://extensions-quarkus-pr-1011-preview.surge.sh/io.quarkiverse.langchain4j/quarkus-langchain4j-core/
• https://extensions-quarkus-pr-1011-preview.surge.sh/org.apache.camel.quarkus/camel-quarkus-kafka/
• https://extensions-quarkus-pr-1011-preview.surge.sh/io.quarkus/quarkus-hibernate-orm/

Open questions:

• Is "sample(s)" the best link name? I can't come up with a better one

[github-actions[bot]]

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