Add skipped test for multi collocation query

For some reason the rpy2py conversion from tibble to pandas data
not work here multi row tibbles:

TypeError: 'NULLType' object is not iterable
Change-Id: I9252263918f2c1e71a384827e483e999b009be01
diff --git a/KorAPClient/tests/test_korapclient.py b/KorAPClient/tests/test_korapclient.py
index 485f513..1b9774e 100644
--- a/KorAPClient/tests/test_korapclient.py
+++ b/KorAPClient/tests/test_korapclient.py
@@ -22,6 +22,9 @@
         self.assertGreater(df['pmi'][0], 10)
         self.assertLess(df['pmi'][0], 20)
 
+    @unittest.skip("Conversion error in rpy2py")
+    def test_collocation_score_query_multi_collocates(self):
+        df = self.kcon.collocationScoreQuery("Ameisenplage", ["einer", "heimgesucht"], leftContextSize=1, rightContextSize=1)
 
     def test_corpus_stats(self):
         df = self.kcon.corpusStats(**{"as.df": True})