ci: Add Code Test Coverage with CodeCov (sourcenetwork#116)

Generates defra's code's testing coverage report and uploads it to CodeCov.

.github/workflows/code-test-coverage.yml

@@ -0,0 +1,33 @@
+name: Code Test Coverage
+
+on: [push]
+
+jobs:
+  code-test-coverage:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 2
+
+      - name: Setup Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.17'
+
+      - name: Generate coverage report
+        run: go test ./... -race -coverprofile=coverage.out -covermode=atomic
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v2
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          fail_ci_if_error: true
+          files: ./coverage.out
+          flags: unittests
+          name: codecov-umbrella
+          verbose: true
+          # path_to_write_report: ./coverage/codecov_report.txt
+          # directory: ./coverage/reports/

README.md

@@ -1,4 +1,6 @@
-<p align="center"> 
+[![codecov](https://codecov.io/gh/sourcenetwork/defradb/branch/develop/graph/badge.svg?token=RHAORX13PA)](https://codecov.io/gh/sourcenetwork/defradb)
+
+<p align="center">
 <img height="120px" src="docs/DefraDB_Full-v2-cropped.png">
 </p>