tests/test_4767.py: don't attempt to run on pyodide.

Author: julian-smith-artifex-com

tests/test_4767.py

@@ -9,6 +9,10 @@ def test_4767():
     '''
     Check handling of unsafe paths in `pymupdf embed-extract`.
     '''
+    if os.environ.get('PYODIDE_ROOT'):
+        print('test_4767(): not running on Pyodide - cannot run child processes.')
+        return
+        
     with pymupdf.open() as document:
         document.new_page() 
         document.embfile_add(