chore: replace codecov with coveralls

.circleci/config.yml

@@ -1,6 +1,8 @@
 # Javascript Node CircleCI 2.0 configuration file
 # Check https://circleci.com/docs/2.0/language-javascript/ for more details
-version: 2
+version: 2.1
+orbs:
+  coveralls: coveralls/coveralls@1.0.6
 jobs:
   build:
     docker:
@@ -43,3 +45,5 @@ jobs:
       - run:
           name: Deploy
           command: ./.circleci/deploy.sh
+
+      - coveralls/upload

README.md

@@ -2,7 +2,7 @@
 > A very experimental UI library built on top of native custom elements
 
 [![CircleCI](https://circleci.com/gh/glorious-codes/glorious-taslonic.svg?style=svg)](https://circleci.com/gh/glorious-codes/glorious-taslonic)
-[![codecov](https://codecov.io/gh/glorious-codes/glorious-taslonic/branch/master/graph/badge.svg)](https://codecov.io/gh/glorious-codes/glorious-taslonic)
+[![Coverage Status](https://coveralls.io/repos/github/glorious-codes/glorious-taslonic/badge.svg)](https://coveralls.io/github/glorious-codes/glorious-taslonic)
 
 ## Early definitions