Try to avoid duplicate Codecov notifications

Author: marcphilipp

.codecov.yml

@@ -5,8 +5,9 @@ coverage:
         threshold: 1
     patch: off
   notify:
+    require_ci_to_pass: no
     slack:
       default:
         url: "secret:F3tyY8zm4BW8W1KD5t4X7atr6OTDT7FNo+UatckerMIidQIWAkO8dJdc7bnNLNSBNIvIPR+3apf+9MMoSrNuscNgHjgAwR7N2PxP5Qpr0O0UNW/ys/ZkG3xiXWg5uAsovDJ137bYM7KgDhguZTQ+vp5RIeaok9FaXkvfjRHz4PM="
         only_pulls: false
-        branches: null
+        branches: master