fix: rebase and rm regression tests from tests

.github/workflows/tests.yml

@@ -71,7 +71,7 @@ jobs:
           exit 1
           fi
 
-    - name: Ensure that the changelog reflects the changes
+    - name: Ensure that the changelog was updated
       id: changelog
       if: always() # Run this step even if the previous one fails
       run: |
@@ -120,36 +120,4 @@ jobs:
     - name: Test with pytest
       run: |
         pip install pytest pytest-cov
-        pytest tests/ -m "not regression" --cov=jaxley --cov-report=xml
-
-  regression_tests:
-    name: Regression Tests
-    runs-on: ubuntu-20.04
-    needs: pytest  # ensure regression tests are only run if tests pass
-
-    steps:
-    - uses: actions/checkout@v3
-      with:
-        lfs: true
-        fetch-depth: 0 # This ensures we can checkout the main branch too
-
-    - uses: actions/setup-python@v4
-      with:
-        python-version: '3.10'
-        architecture: 'x64'
-
-    - name: Install dependencies
-      run: |
-        python -m pip install --upgrade pip
-        pip install -e ".[dev]"
-
-    - name: Run benchmarks and compare to baseline
-      if: github.event.pull_request.base.ref == 'main'  # Run only for PRs targeting the 'main' branch
-      run: |
-        # Check if regression test results exist in main branch
-        if git cat-file -e main:tests/regression_test_baselines.json; then
-          git checkout main tests/regression_test_baselines.json
-        else
-          echo "No regression test results found in main branch"
-        fi
-        pytest -m regression
+        pytest tests/ -m "not regression" --cov=jaxley --cov-report=xml