Bump andstor/file-existence-action from 2 to 3

Bumps [andstor/file-existence-action](https://github.com/andstor/file-existence-action) from 2 to 3.
- [Release notes](https://github.com/andstor/file-existence-action/releases)
- [Commits](andstor/file-existence-action@v2...v3)

---
updated-dependencies:
- dependency-name: andstor/file-existence-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/build.yml

@@ -30,7 +30,7 @@ jobs:
 
     - name: Check for 'lcov.info' existence
       id: check_files
-      uses: andstor/file-existence-action@v2
+      uses: andstor/file-existence-action@v3
       with:
         files: "TestResults/reports/lcov.info"