[Fix]Fix pt version for merge stage test (#2449)

## Motivation

The conflict is caused by:
    The user requested torch==1.12.1+cpu
    torchvision 0.13.0+cpu depends on torch==1.12.0

## Modification

modify the torch==1.12.0+cpu

.github/workflows/merge_stage_test.yml

@@ -37,9 +37,6 @@ jobs:
         run: |
           pip install pip --upgrade
           pip install wheel
-      - name: Install Pillow
-        run: pip install Pillow==6.2.2
-        if: ${{matrix.torchvision == '0.4.2'}}
       - name: Install PyTorch
         run: pip install torch==${{matrix.torch}}+cpu torchvision==${{matrix.torchvision}}+cpu -f https://download.pytorch.org/whl/torch_stable.html
       - name: Install mmseg dependencies
@@ -65,7 +62,8 @@ jobs:
     strategy:
       matrix:
         python-version: [3.7]
-        torch: [1.6.0, 1.7.1, 1.8.1, 1.9.1, 1.10.1, 1.11.0, 1.12.1, 1.13.0]
+        torch: [1.6.0, 1.7.1, 1.8.1, 1.9.1, 1.10.1, 1.11.0, 1.12.0]
+        # torch: [1.6.0, 1.7.1, 1.8.1, 1.9.1, 1.10.1, 1.11.0, 1.12.0, 1.13.0]
         include:
           - torch: 1.6.0
             torchvision: 0.7.0
@@ -79,10 +77,10 @@ jobs:
             torchvision: 0.11.2
           - torch: 1.11.0
             torchvision: 0.12.0
-          - torch: 1.12.1
+          - torch: 1.12.0
             torchvision: 0.13.0
-          - torch: 1.13.0
-            torchvision:
+          # - torch: 1.13.0
+          #   torchvision: 0.14.0
     steps:
       - uses: actions/checkout@v2
       - name: Set up Python ${{ matrix.python-version }}
@@ -111,18 +109,19 @@ jobs:
         run: rm -rf .eggs && pip install -e .
       - name: Run unittests and generate coverage report
         # timm from v0.6.11 requires torch>=1.7
-        if: ${{matrix.torch >= '1.7.0'}}
+        if: ${{matrix.torch != '1.6.0'}}
         run: |
           pip install timm
           coverage run --branch --source mmseg -m pytest tests/
           coverage xml
           coverage report -m
       - name: Skip timm unittests and generate coverage report
+        if: ${{matrix.torch == '1.6.0'}}
         run: |
           coverage run --branch --source mmseg -m pytest tests/ --ignore tests/test_models/test_backbones/test_timm_backbone.py
           coverage xml
           coverage report -m
-      # Only upload coverage report for python3.7 && pytorch1.8.1 without timm
+      # Only upload coverage report for python3.7 && pytorch1.8.1 with timm
       - name: Upload coverage to Codecov
         if: ${{matrix.torch == '1.8.1' && matrix.python-version == '3.7'}}
         uses: codecov/codecov-action@v2
@@ -159,7 +158,6 @@ jobs:
           apt-key adv --fetch-keys https://developer.download.nvidia.com/compute/machine-learning/repos/ubuntu1804/x86_64/7fa2af80.pub
       - name: Install Python-dev
         run: apt-get update && apt-get install -y python${{matrix.python-version}}-dev
-        if: ${{matrix.python-version != 3.9}}
       - name: Install system dependencies
         run: |
           apt-get update && apt-get install -y ffmpeg libsm6 libxext6 git ninja-build libglib2.0-0 libsm6 libxrender-dev libxext6
@@ -203,7 +201,6 @@ jobs:
           apt-key adv --fetch-keys https://developer.download.nvidia.com/compute/machine-learning/repos/ubuntu1804/x86_64/7fa2af80.pub
       - name: Install Python-dev
         run: apt-get update && apt-get install -y python${{matrix.python-version}}-dev
-        if: ${{matrix.python-version != 3.9}}
       - name: Install system dependencies
         run: |
           apt-get update && apt-get install -y ffmpeg libsm6 libxext6 git ninja-build libglib2.0-0 libsm6 libxrender-dev libxext6

.github/workflows/pr_stage_test.yml

@@ -53,10 +53,11 @@ jobs:
         run: rm -rf .eggs && pip install -e .
       - name: Run unittests and generate coverage report
         run: |
-          coverage run --branch --source mmseg -m pytest tests/ --ignore tests/test_models/test_backbones/test_timm_backbone.py
+          pip install timm
+          coverage run --branch --source mmseg -m pytest tests/
           coverage xml
           coverage report -m
-      # Upload coverage report for python3.7 && pytorch1.8.1 cpu without timm
+      # Upload coverage report for python3.7 && pytorch1.8.1 cpu with timm
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v1.0.14
         with: