test: add codecov configuration (#51)

Author: ReenigneArcher

README.md

@@ -1,6 +1,7 @@
 # ContribKit for LizardByte
 
-## About
+[![GitHub Workflow Status (CI)](https://img.shields.io/github/actions/workflow/status/lizardbyte/contributors/_ci-node.yml.svg?branch=master&label=CI%20build&logo=github&style=for-the-badge)](https://github.com/LizardByte/contributors/actions/workflows/_ci_node.yml?query=branch%3Amaster)
+[![Codecov](https://img.shields.io/codecov/c/gh/LizardByte/contributors?token=OM7a9eaeAs&style=for-the-badge&logo=codecov&label=codecov)](https://codecov.io/gh/LizardByte/contributors)
 
 This repository was generated from [sponsorkit-starter](https://github.com/Open-reSource/sponsorkit-starter)
 and uses [ContribKit](https://github.com/LizardByte/contribkit/) toolkit for automatically generating contributor

codecov.yml

@@ -0,0 +1,19 @@
+---
+codecov:
+  branch: master
+
+coverage:
+  status:
+    project:
+      default:
+        target: auto
+        threshold: 10%
+
+comment:
+  layout: "diff, flags, files"
+  behavior: default
+  require_changes: false  # if true: only post the comment if coverage changes
+
+ignore:
+  - "tests"
+  - "third-party"