Fix CI by installing ROOT from conda-forge

.github/workflows/ci.yaml

@@ -16,16 +16,13 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest]
-        # Python doesn't matter, conda had been built only with 3.8.5
-        python-version: ["3.8"]
 
     steps:
-    - uses: actions/checkout@v2
-    - name: Set up Python ${{ matrix.python-version }} (Miniconda)
-      uses: conda-incubator/setup-miniconda@v2
+    - uses: actions/checkout@v4
+    - name: Set up Miniconda
+      uses: conda-incubator/setup-miniconda@v3
       with:
         auto-update-conda: true
-        python-version: ${{ matrix.python-version }}
 
     - name: Conda info
       shell: bash -l {0}
@@ -39,21 +36,20 @@ jobs:
     - name: Conda install dependencies
       shell: bash -l {0}
       run: |
-           conda create -n root-nightly -y -c https://root.cern/download/conda-nightly/latest -c conda-forge root-nightly cmake pytest pytest-benchmark pytest-csv numpy numba
+           conda create -n rootbench -y -c conda-forge root cmake pytest pytest-benchmark pytest-csv numpy numba
 
     - name: Configure and build
       shell: bash -l {0}
       run: |
-           conda activate root-nightly
+           conda activate rootbench
            mkdir -p build && cd build
            cmake -Dcuda=OFF ..
-           cmake --build .
+           cmake --build . -j $(nproc)
 
     - name: Run benchmarks
       shell: bash -l {0}
       run: |
-           conda activate root-nightly
-           export PYTHONHOME=$CONDA
+           conda activate rootbench
            export RB_TEMP_FS=.
            cd build
            ctest -V