Improve test coverage from 63.6% to 73.4% and fix test infrastructure (#137)

.github/workflows/tests.yml

@@ -25,16 +25,21 @@ jobs:
           cache: "pip"
 
       - name: Install dependencies
-        run: pip install -e ".[dev]"
+        run: |
+          pip install poetry
+          poetry install --with dev
 
       - name: Run tests
         run: |
           mkdir -p reports
-          pytest \
+          poetry run pytest \
             --cov=src \
             --cov-report=term-missing \
             --cov-report=xml:reports/coverage.xml \
-            --junitxml=reports/junit.xml
+            --cov-fail-under=73 \
+            --junitxml=reports/junit.xml \
+            -p no:xdist \
+            -m "not ollama and not docker and not selenium and not external_api"
 
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