chore(ci): breakout FOSSA provided build action (#36)

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<!-- Provide a brief summary of the changes -->

## Description
<!-- Provide a detailed description of the changes -->

This PR breaks the FOSSA GitHub Action out into its own workflow, which
will only run when changes are merged to `main.` This will avoid checks
breaking PRs for external contributors.

## References
<!-- Provide a list of any applicable references here (GitHub Issue,
[OpenFGA RFC](https://github.com/openfga/rfcs), other PRs, etc..) -->

## Review Checklist
- [x] I have clicked on ["allow edits by
maintainers"](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/allowing-changes-to-a-pull-request-branch-created-from-a-fork).
- [ ] I have added documentation for new/changed functionality in this
PR or in a PR to [openfga.dev](https://github.com/openfga/openfga.dev)
[Provide a link to any relevant PRs in the references section above]
- [x] The correct base branch is being used, if not `main`
- [ ] I have added tests to validate that the change in functionality is
working as expected

.github/workflows/checks.yaml

@@ -7,28 +7,6 @@ on:
   workflow_dispatch:
 
 jobs:
-  fossa:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Set up JDK 17
-        uses: actions/setup-java@v4
-        with:
-          java-version: "17"
-          distribution: "temurin"
-      - name: Install dependencies
-        run: ./gradlew build
-      - name: Run FOSSA scan and upload build data
-        uses: fossas/fossa-action@main
-        with:
-          api-key: ${{ secrets.FOSSA_API_KEY }}
-          branch: ${{ github.ref_name }}
-      - name: Run FOSSA tests
-        uses: fossas/fossa-action@main
-        with:
-          api-key: ${{ secrets.FOSSA_API_KEY }}
-          run-tests: true
-
   test:
     name: Run Checks
     runs-on: ubuntu-latest
@@ -40,12 +18,15 @@ jobs:
     steps:
       - name: Checkout the source
         uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+
       - name: Validate Gradle wrapper
         uses: gradle/wrapper-validation-action@b231772637bb498f11fdbc86052b6e8a8dc9fc92 # v2.1.2
+
       - name: Set up JDK
         uses: actions/setup-java@99b8673ff64fbf99d8d325f52d9a5bdedb8483e9 # v4.2.1
         with:
           java-version: ${{ matrix.java }}
           distribution: "temurin"
+
       - name: Run Gradle check task
         run: ./gradlew check --continue

.github/workflows/fossa.yaml

@@ -0,0 +1,35 @@
+name: FOSSA
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+
+jobs:
+  fossa:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v4
+        with:
+          java-version: "17"
+          distribution: "temurin"
+
+      - name: Install dependencies
+        run: ./gradlew build
+
+      - name: Run FOSSA scan and upload build data
+        uses: fossas/fossa-action@main
+        with:
+          api-key: ${{ secrets.FOSSA_API_KEY }}
+          branch: ${{ github.ref_name }}
+
+      - name: Run FOSSA tests
+        uses: fossas/fossa-action@main
+        with:
+          api-key: ${{ secrets.FOSSA_API_KEY }}
+          run-tests: true