Try PCH=ON CCACHE=OFF (#329)

This should make AC build faster for us. (new: 23 min, old: 39 min)

.github/workflows/build.yml

@@ -47,11 +47,7 @@ jobs:
   AC-Eluna:
     strategy:
       fail-fast: false
-      matrix:
-        compiler: [clang10]
     runs-on: ubuntu-20.04
-    env:
-      COMPILER: ${{ matrix.compiler }}
     steps:
       - uses: actions/checkout@v2
         with:
@@ -66,18 +62,35 @@ jobs:
       - uses: actions/checkout@v2
         with:
           path: modules/mod-eluna-lua-engine/LuaEngine
-      - name: Cache
-        uses: actions/cache@v2
-        with:
-          path: /home/runner/.ccache
-          key: ccache:${{ matrix.compiler }}:${{ github.ref }}:${{ github.sha }}
-          restore-keys: |
-            ccache:${{ matrix.compiler }}:${{ github.ref }}
-            ccache:${{ matrix.compiler }}
       - name: Configure OS
-        run: source ./apps/ci/ci-install.sh
-        env:
-          CONTINUOUS_INTEGRATION: true
+        run: |
+          # Copy paste of https://github.com/azerothcore/azerothcore-wotlk/blob/master/apps/ci/ci-install.sh
+
+          cat >>conf/config.sh <<CONFIG_SH
+          MTHREADS=4
+          CWARNINGS=ON
+          CDEBUG=OFF
+          CTYPE=Release
+          CSCRIPTS=ON
+          CUNIT_TESTS=ON
+          CSERVERS=ON
+          CTOOLS=ON
+          CSCRIPTPCH=ON
+          CCOREPCH=ON
+          CCUSTOMOPTIONS='-DCMAKE_C_FLAGS="-Werror" -DCMAKE_CXX_FLAGS="-Werror"'
+          DB_CHARACTERS_CONF="MYSQL_USER='root'; MYSQL_PASS='root'; MYSQL_HOST='localhost';"
+          DB_AUTH_CONF="MYSQL_USER='root'; MYSQL_PASS='root'; MYSQL_HOST='localhost';"
+          DB_WORLD_CONF="MYSQL_USER='root'; MYSQL_PASS='root'; MYSQL_HOST='localhost';"
+          CONFIG_SH
+
+          time sudo apt-get update -y
+          # time sudo apt-get upgrade -y
+          time sudo apt-get install -y git lsb-release sudo ccache
+          time ./acore.sh install-deps
+
+          time sudo apt-get install -y clang-10
+          echo "CCOMPILERC=\"clang-10\"" >> ./conf/config.sh
+          echo "CCOMPILERCXX=\"clang++-10\"" >> ./conf/config.sh
       - name: Import db
         run: source ./apps/ci/ci-import-db.sh
       - name: Build