docs: improve the docs and API param name (#1629)

Signed-off-by: BubbleCal <bubble-cal@outlook.com>

python/python/lancedb/table.py

@@ -505,7 +505,7 @@ class Table(ABC):
             Only available with use_tantivy=False
             If False, do not store the positions of the terms in the text.
             This can reduce the size of the index and improve indexing speed.
-            But it will not be possible to use phrase queries.
+            But it will raise an exception for phrase queries.
 
         """
         raise NotImplementedError

python/python/tests/test_fts.py

@@ -143,7 +143,7 @@ def test_create_index_with_stemming(tmp_path, table):
 @pytest.mark.parametrize("with_position", [True, False])
 def test_create_inverted_index(table, use_tantivy, with_position):
     if use_tantivy and not with_position:
-        pytest.skip("we don't support to build tantivy index without position")
+        pytest.skip("we don't support building a tantivy index without position")
     table.create_fts_index("text", use_tantivy=use_tantivy, with_position=with_position)