Skipp jupyter extensions test

conftest.py

@@ -99,7 +99,7 @@ except ImportError:
     collect_ignore += [os.path.join(SCRIPT_FOLDER, "pystencils/datahandling/vtk.py")]
 
 # TODO: Remove if Ubuntu 18.04 is no longer supported
-if pytest_version >= 50403:
+if pytest_version < 50403:
     collect_ignore += [os.path.join(SCRIPT_FOLDER, "pystencils_tests/test_jupyter_extensions.ipynb")]
 
 collect_ignore += [os.path.join(SCRIPT_FOLDER, 'setup.py')]

pystencils_tests/test_basic_usage_llvm.ipynb

@@ -390,7 +390,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.6.5"
+   "version": "3.8.5"
   }
  },
  "nbformat": 4,

pystencils_tests/test_phasefield_dentritic_3D.ipynb

@@ -369,7 +369,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.6.9"
+   "version": "3.8.5"
   }
  },
  "nbformat": 4,