Properly Build Spectra via ShadowProver in GH Action

.github/workflows/build.yml

@@ -10,17 +10,25 @@ on:
 jobs:
   build:
     runs-on: ubuntu-latest
+    
     steps:
-    - name: Checkout
-      uses: actions/checkout@v3
-
     - name: Set up JDK 8
       uses: actions/setup-java@v3
       with:
-        java-version: '8'
+        java-version: '17'
         distribution: 'temurin'
+    
+    - name: Install ShadowProver
+      run: |
+        git clone https://github.com/rairlab/shadowprover
+        cd shadowprover
+        mvn package install
+    
+    - name: Checkout Spectra
+      uses: actions/checkout@v3
+      with:
+        submodules: true
+        fetch-depth: 0
 
     - name: Build With Maven
       run: mvn package
-    
-