fix(ci): use uv to run commands

Author: juhannc

.github/workflows/flake8.yml

@@ -33,4 +33,4 @@ jobs:
           uv sync --group ci
       - name: Lint with flake8
         run: |
-          flake8 pycasx
+          uv run flake8 src/pycasx

.github/workflows/pylint.yml

@@ -30,4 +30,4 @@ jobs:
           uv sync --group ci
       - name: Analysing the code with pylint
         run: |
-          pylint --output-format=text pycasx
+          uv run pylint --output-format=text src/pycasx

.github/workflows/pytest.yml

@@ -36,4 +36,4 @@ jobs:
           uv sync --group tests
       - name: Test with pytest
         run: |
-          pytest
+          uv run pytest