feat: update matrix action to v3.0 (#353)

### Description

This is not a breaking change for the reusable workflow, updating
version of the action to v3.0.

This PR will be followed up with a template change.

Tested - splunk/addonfactory-ucc-generator#1525.

### Checklist

- [x] `README.md` has been updated or is not required
- [ ] push trigger tests
- [ ] manual release test
- [ ] automated releaes test
- [ ] pull request trigger tests
- [ ] schedule trigger tests
- [ ] workflow errors/warnings reviewed and addressed

### Testing done 
(for each selected checkbox, the corresponding test results link should
be listed here)

.github/workflows/reusable-build-test-release.yml

@@ -239,7 +239,7 @@ jobs:
           submodules: false
           persist-credentials: false
       - id: matrix
-        uses: splunk/addonfactory-test-matrix-action@v2.1
+        uses: splunk/addonfactory-test-matrix-action@v3.0
       - name: job summary
         run: |
           splunk_version_list=$(echo '${{ steps.matrix.outputs.supportedSplunk }}' | jq -r '.[].version')