simplify ci like actix-web (#165)

codecov.yml

@@ -1,7 +1,16 @@
 comment: false
 
-ignore: # ignore codecoverage on following paths
+coverage:
+  status:
+    project:
+      default:
+        threshold: 100% # make CI green
+    patch:
+      default:
+        threshold: 100% # make CI green
+
+# ignore code coverage on following paths
+ignore:
+  - "**/tests"
+  - "**/benches"
   - "**/examples"
-  - ".github"
-  - "**/*.md"
-  - "**/*.toml"