Pass unmatched requests, not the default hash

Add retries for 503s in case we have slow responses on media proxy
2 jobs from varnish-improvements in 6 minutes and 46 seconds (queued for 3 seconds)
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Status Job ID Name Coverage
  Lint
passed #13645
lint

00:04:09

 
  Test
passed #13646
unit-testing

00:02:37