add other ignore files; and remove go test --race

Author: arvindbr8

.github/codecov.yml

@@ -1,16 +1,27 @@
 coverage:
   status:
-    patch:
-      default:
-        target: "80"
     project:
       default:
-        target: auto
-        threshold: 1
+        informational: true
+    patch:
+      default:
+        informational: true
 ignore:
-  - "test/"
-  - "benchmark/"
-  - "internal/testutils"
-  - ".*.pb.go"
+  - "benchmark/**/*"
+  - "stress/**/*"
+  # All 'pb.go's
+  - "**/*.pb.go"
+  # Tests and test related files.
+  - "test/**/*"
+  - "xds/internal/testutils/**/*"
+  - "xds/internal/test/**/*"
+  - "balancer/rls/internal/test/e2e/**/*"
+  - "testdata"
+  # Other submodules.
+  - "security/**/*"
+  - "examples/**/*"
+  - "interop/**/*"
+  - "stats/**/*"
+  - "gcp/**/*"
 comment:
-  layout: "header"
+  layout: "header, diff, files"