chore: fixups

Author: clintval

.github/workflows/build_seshat_exe.yml

@@ -19,7 +19,7 @@ jobs:
       - uses: actions/setup-java@v4
         with:
           distribution: 'temurin'
-          java-version: ${{ matrix.JAVA_VERSION }}
+          java-version: 21
 
       - name: Cache for Scala Dependencies
         uses: actions/cache@v4
@@ -28,7 +28,7 @@ jobs:
             ~/.mill/download
             ~/.m2/repository
             ~/.cache/coursier
-          key: ${{ runner.os }}-java-mill-${{ matrix.JAVA_VERSION }}-${{ hashFiles('**/build.sc') }}
+          key: ${{ runner.os }}-java-mill-21-${{ hashFiles('**/build.sc') }}
           restore-keys: ${{ runner.os }}-java-mill-
 
       - name: Compile Scala Code