TEST-#2020: decrease parallel tests on Ubuntu (#2021)

Signed-off-by: Anatoly Myachev <anatoly.myachev@intel.com>

Author: anmyachev

.github/workflows/ci.yml

@@ -172,11 +172,10 @@ jobs:
       matrix:
         python-version: ["3.6", "3.7", "3.8"]
         engine: ["python", "ray", "dask"]
-        part: ["reduction", "binary", "map_metadata", "udf", "default", "window", "indexing", "iter", "join_sort", 3]
     env:
       MODIN_ENGINE: ${{matrix.engine}}
       MODIN_MEMORY: 1000000000
-    name: test (${{matrix.engine}}, part ${{matrix.part}}, python ${{matrix.python-version}})
+    name: test-ubuntu (engine ${{matrix.engine}}, python ${{matrix.python-version}})
     steps:
       - uses: actions/checkout@v2
         with:
@@ -199,35 +198,41 @@ jobs:
           conda info
           conda list
       - name: Install HDF5
-        if: matrix.part == 3
         run: sudo apt update && sudo apt install -y libhdf5-dev
       - shell: bash -l {0}
-        run: pytest modin/pandas/test/dataframe/test_${{matrix.part}}.py
-        if: matrix.part != 3
+        run: pytest modin/pandas/test/dataframe/test_binary.py
+      - shell: bash -l {0}
+        run: pytest modin/pandas/test/dataframe/test_default.py
+      - shell: bash -l {0}
+        run: pytest modin/pandas/test/dataframe/test_indexing.py
+      - shell: bash -l {0}
+        run: pytest modin/pandas/test/dataframe/test_iter.py
+      - shell: bash -l {0}
+        run: pytest modin/pandas/test/dataframe/test_join_sort.py
+      - shell: bash -l {0}
+        run: pytest modin/pandas/test/dataframe/test_map_metadata.py
+      - shell: bash -l {0}
+        run: pytest modin/pandas/test/dataframe/test_reduction.py
+      - shell: bash -l {0}
+        run: pytest modin/pandas/test/dataframe/test_udf.py
+      - shell: bash -l {0}
+        run: pytest modin/pandas/test/dataframe/test_window.py
       - shell: bash -l {0}
         run: python -m pytest modin/pandas/test/test_series.py
-        if: matrix.part == 3
       - shell: bash -l {0}
         run: python -m pytest modin/pandas/test/test_rolling.py
-        if: matrix.part == 3
       - shell: bash -l {0}
         run: python -m pytest modin/pandas/test/test_concat.py
-        if: matrix.part == 3
       - shell: bash -l {0}
         run: python -m pytest modin/pandas/test/test_groupby.py
-        if: matrix.part == 3
       - shell: bash -l {0}
         run: python -m pytest modin/pandas/test/test_reshape.py
-        if: matrix.part == 3
       - shell: bash -l {0}
         run: python -m pytest modin/pandas/test/test_general.py
-        if: matrix.part == 3
       - shell: bash -l {0}
         run: python -m pytest modin/pandas/test/test_io.py
-        if: matrix.part == 3
       - shell: bash -l {0}
         run: python -m pytest modin/experimental/pandas/test/test_io_exp.py
-        if: matrix.part == 3
       - shell: bash -l {0}
         run: bash <(curl -s https://codecov.io/bash)