Chore(deps): Bump andstor/file-existence-action from 2.0.0 to 3.0.0

Bumps [andstor/file-existence-action](https://github.com/andstor/file-existence-action) from 2.0.0 to 3.0.0.
- [Release notes](https://github.com/andstor/file-existence-action/releases)
- [Commits](20b4d2e596...076e007279)

---
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>

.github/workflows/appstore-build-publish.yml

@@ -75,7 +75,7 @@ jobs:
 
       - name: Check composer.json
         id: check_composer
-        uses: andstor/file-existence-action@20b4d2e596410855db8f9ca21e96fbe18e12930b # v2
+        uses: andstor/file-existence-action@076e0072799f4942c8bc574a82233e1e4d13e9d6 # v2
         with:
           files: "${{ env.APP_NAME }}/composer.json"
 
@@ -97,7 +97,7 @@ jobs:
 
       - name: Check Krankerl config
         id: krankerl
-        uses: andstor/file-existence-action@20b4d2e596410855db8f9ca21e96fbe18e12930b # v2
+        uses: andstor/file-existence-action@076e0072799f4942c8bc574a82233e1e4d13e9d6 # v2
         with:
           files: ${{ env.APP_NAME }}/krankerl.toml