remove scala app test for nightly test

.github/workflows/nightly_test.yml

@@ -19,7 +19,6 @@ on:
         - Orca-Python-Ray-Py37-Spark3
         - Orca-Python-Py37-Spark3
         - Orca-Ray-Ctx-Example
-        - Scala-App
         - Dllib-Scala-UT
         - Friesian-Scala-UT
         - PPML-Scala-UT
@@ -96,40 +95,6 @@ jobs:
     - name: Run test
       uses: ./.github/actions/orca-python-py37-spark3-action
 
-  Scala-App:
-    if: ${{ github.event.schedule || github.event.inputs.artifact == 'Scala-App' || github.event.inputs.artifact == 'all' }} 
-    runs-on: [self-hosted, Gondolin, ubuntu-20.04-lts]
-
-    steps:
-    - uses: actions/checkout@v3
-    - name: Set up JDK8
-      uses: ./.github/actions/jdk-setup-action
-    - name: Set up maven
-      uses: ./.github/actions/maven-setup-action
-    - name: Set up Python 
-      uses: actions/setup-python@v2
-      with:
-        python-version: '3.7'
-    - name: Install dependencies
-      run: |
-        python -m pip install --upgrade pip
-        pip install numpy
-        pip install tensorflow==1.15.0
-        pip install jupyter
-        apt-get update
-        apt-get install wget 
-
-        wget https://downloads.lightbend.com/scala/2.11.8/scala-2.11.8.tgz
-        gunzip scala-2.11.8.tgz
-        tar -xf scala-2.11.8.tar -C /opt
-        rm scala-2.11.8.tar
-        ln -s /opt/scala-2.11.8 /opt/scala
-    - name: Run Test
-      run: |
-          export SCALA_HOME=/opt/scala
-          chmod a+x apps/run-scala-app-test.sh
-          apps/run-scala-app-test.sh
-
   Dllib-Scala-UT:
     if: ${{ github.event.schedule || github.event.inputs.artifact == 'Dllib-Scala-UT' || github.event.inputs.artifact == 'all' }} 
     runs-on: [ self-hosted, Gondolin, ubuntu-20.04-lts ]