chore: update inputs.ts adding comment about fetch_depth (#2000)

src/inputs.ts

@@ -297,6 +297,7 @@ export const getInputs = (): Inputs => {
   }
 
   if (fetchDepth) {
+    // Fallback to at least 2 if the fetch_depth is less than 2
     inputs.fetchDepth = Math.max(parseInt(fetchDepth, 10), 2)
   }