chore: migrate to codecov (#388)

# Description

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# Pull Request Type

Please select the option(s) that are relevant to this PR.

- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
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- [ ] Improvement (fixing a typo, updating readme, renaming a variable
name, etc)

Author: Justintime50

.github/workflows/ci.yml

@@ -35,12 +35,11 @@ jobs:
         run: just install
       - name: Run Tests
         run: EASYPOST_TEST_API_KEY=123 EASYPOST_PROD_API_KEY=123 just coverage
-      - name: Coveralls
+      - name: Coverage
         if: github.ref == 'refs/heads/master'
-        uses: coverallsapp/github-action@master
+        uses: codecov/codecov-action@v5
         with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-          path-to-lcov: './coverage.lcov'
+          token: ${{ secrets.CODECOV_TOKEN }}
       - name: Run security analysis
         run: just scan
   docs:

README.md

@@ -1,7 +1,7 @@
 # EasyPost Python Client Library
 
 [![CI](https://github.com/EasyPost/easypost-python/workflows/CI/badge.svg)](https://github.com/EasyPost/easypost-python/actions?query=workflow%3ACI)
-[![Coverage Status](https://coveralls.io/repos/github/EasyPost/easypost-python/badge.svg)](https://coveralls.io/github/EasyPost/easypost-python)
+[![codecov](https://codecov.io/gh/EasyPost/easypost-python/graph/badge.svg?token=SxXsqBjQUb)](https://codecov.io/gh/EasyPost/easypost-python)
 [![PyPI version](https://badge.fury.io/py/easypost.svg)](https://badge.fury.io/py/easypost)
 
 EasyPost, the simple shipping solution. You can sign up for an account at <https://easypost.com>.