ci: default to 1 day for lookback PRs for post validation (#124)

Author: jvbriones

.github/workflows/post-merge-validation.yml

@@ -20,7 +20,7 @@ on:
         description: 'Number of days to look back for PRs'
         required: false
         type: number
-        default: 2
+        default: 1
     secrets:
       github-token:
         description: 'GitHub token with repo access'