Remove unused flake8-matcher.json

- removes unused flake8-matcher.json
- change from pip to uv pip in github benchmark

.github/workflows/benchmark.yml

@@ -10,6 +10,11 @@ permissions:
     # contents permission to update benchmark contents in gh-pages branch
     contents: write
 
+env:
+  ERT_SHOW_BACKTRACE: 1
+  ECL_SKIP_SIGNAL: 1
+  UV_SYSTEM_PYTHON: 1
+
 jobs:
   benchmark:
     name: Run pytest-benchmark benchmark example
@@ -27,13 +32,13 @@ jobs:
         with:
           # pin this to maintain comparable benchmark results
           python-version: "3.10"
-          cache: "pip"
-          cache-dependency-path: |
-            pyproject.toml
+
+      - name: Install uv
+        run: pip install uv
 
       - name: Install ert with dev-deps
         run: |
-          pip install ".[dev]"
+          uv pip install ".[dev]"
 
       - name: Run benchmark
         run: |

.github/workflows/style.yml

@@ -39,9 +39,6 @@ jobs:
       run: |
         uv pip install ".[style]"
 
-    - name: Add matching rule
-      run: echo ::add-matcher::.github/flake8-matcher.json
-
     - name: Run style check
       if: ${{ always() }}
       run: |