chore: migrate to codecov (#375)

# Description

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# Testing

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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

@@ -56,12 +56,11 @@ jobs:
       - name: Convert coverage report
         if: github.ref == 'refs/heads/master'
         run: grcov target/site/jacoco/jacoco.xml --source-dir ./ --ignore "target/*" > coverage.lcov
-      - 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 }}
   lint:
     runs-on: ubuntu-latest
     steps:

README.md

@@ -1,7 +1,7 @@
 # EasyPost Java Client Library
 
 [![CI](https://github.com/EasyPost/easypost-java/workflows/CI/badge.svg)](https://github.com/EasyPost/easypost-java/actions?query=workflow%3ACI)
-[![Coverage Status](https://coveralls.io/repos/github/EasyPost/easypost-java/badge.svg?branch=master)](https://coveralls.io/github/EasyPost/easypost-java?branch=master)
+[![codecov](https://codecov.io/gh/EasyPost/easypost-java/graph/badge.svg?token=IWvskosvvO)](https://codecov.io/gh/EasyPost/easypost-java)
 [![Maven Central](https://img.shields.io/maven-central/v/com.easypost/easypost-api-client?label=Maven%20Central)](https://central.sonatype.dev/search?q=easypost-api-client)
 
 EasyPost, the simple shipping solution. You can sign up for an account at <https://easypost.com>.