fix typo in app.py

app.py

@@ -5,7 +5,7 @@ qa_pipe = pipeline('question-answering')
 context = st.text_area('provide context')
 question = st.text_area('ask your question')
 
-if text and context:
+if question and context:
     out = qa_pipe(dict(
         question=question,
         context=context