Add codecov setting for test coverage check

.github/workflows/go.yml

@@ -17,9 +17,15 @@ jobs:
         go-version: 1.15
     - name: Check-out code
       uses: actions/checkout@v2
+      with:
+        fetch-depth: 2
     - name: Run unit tests
       run: |
         make test
+    - name: Upload coverage to Codecov
+      uses: codecov/codecov-action@v3
+      with:
+        file: coverage.txt
 
   tidy:
     runs-on: [ubuntu-latest]

Makefile

@@ -4,7 +4,7 @@ all: test
 
 .PHONY: test
 test:
-	$(GO) test -v ./...
+	$(GO) test -v -coverprofile coverage.txt -covermode=atomic -coverpkg=antrea.io/libOpenflow/common/...,antrea.io/libOpenflow/openflow15/...,antrea.io/libOpenflow/protocol/...,antrea.io/libOpenflow/util/...  antrea.io/libOpenflow/...
 
 # code linting
 .golangci-bin:

codecov.yaml

@@ -0,0 +1,32 @@
+codecov:
+  branch: main
+  require_ci_to_pass: no
+
+comment:
+  layout: "reach,diff,flags,tree"
+  behavior: default
+  require_changes: no
+  require_base: no
+  require_head: no
+  after_n_builds: 1
+  show_carryforward_flags: true
+
+github_checks:
+  annotations: true
+
+coverage:
+  status:
+    patch:
+      default:
+        target: 70%
+        threshold: 5%
+        base: auto
+        only_pulls: false
+    project:
+      default:
+        target: auto
+        threshold: 0.1%
+
+flag_management:
+  default_rules:
+    carryforward: true