Use codecov instead of coveralls

.codecov.yml

@@ -0,0 +1,5 @@
+coverage:
+  status:
+    patch:
+      default:
+        target: 80%

.github/workflows/tests.yml

@@ -57,8 +57,6 @@ jobs:
         run: npm test
         if: success()
 
-      - name: Coveralls
-        uses: coverallsapp/github-action@master
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Upload code coverage
+        uses: codecov/codecov-action@v2
         if: success()

README.md

@@ -7,7 +7,7 @@
 
 <p>
    <a href="https://github.com/weyoss/redis-smq/actions/workflows/tests.yml"><img src="https://github.com/weyoss/redis-smq/actions/workflows/tests.yml/badge.svg" alt="Tests" style="max-width:100%;" /></a>
-   <a href="https://coveralls.io/r/weyoss/redis-smq?branch=master" rel="nofollow"><img src="https://img.shields.io/coveralls/github/weyoss/redis-smq.svg" alt="Coverage Status" /></a>
+   <a href="https://codecov.io/github/weyoss/redis-smq?branch=master" rel="nofollow"><img src="https://img.shields.io/codecov/c/github/weyoss/redis-smq" alt="Coverage Status" /></a>
    <a href="https://npmjs.org/package/redis-smq" rel="nofollow"><img src="https://img.shields.io/npm/v/redis-smq.svg" alt="NPM version" /></a>
    <a href="https://npmjs.org/package/redis-smq" rel="nofollow"><img src="https://img.shields.io/npm/dm/redis-smq.svg" alt="NPM downloads" /></a>
    <a href="https://lgtm.com/projects/g/weyoss/redis-smq/context:javascript" rel="nofollow"><img src="https://img.shields.io/lgtm/grade/javascript/github/weyoss/redis-smq.svg?logo=lgtm&logoWidth=18" alt="Code quality" /></a>