updating artifact not found error message to include more information and link to FAQ

src/internal/find/get-artifact.ts

@@ -49,7 +49,9 @@ export async function getArtifactPublic(
 
   if (getArtifactResp.data.artifacts.length === 0) {
     throw new ArtifactNotFoundError(
-      `Artifact not found for name: ${artifactName}`
+      `Artifact not found for name: ${artifactName}\n
+        Please ensure that your artifact is not expired and the artifact was uploaded using a compatible version of toolkit/upload-artifact.\n
+        For more information, visit the Github Artifacts FAQ: https://github.com/actions/toolkit/blob/main/packages/artifact/docs/faq.md`
     )
   }