ci: disable xash-extras fetching, it's a submodule now

.github/workflows/c-cpp.yml

@@ -51,18 +51,10 @@ jobs:
       uses: actions/checkout@v3
       with:
         submodules: recursive
-    - name: Checkout xash-extras
-      uses: actions/checkout@v3
-      with:
-        repository: FWGS/xash-extras
-        path: xash-extras
-
     - name: Install dependencies
       run: bash scripts/gha/deps_${{ matrix.targetos }}.sh
-
     - name: Build engine
       run: bash scripts/gha/build_${{ matrix.targetos }}.sh
-
     - name: Upload engine (prereleases)
       run: bash scripts/continious_upload.sh artifacts/*
     - name: Upload engine (artifacts)