docs: remove code-block:: python from docs (#1366)

- refer #1264
- fixed minor documentation issue

python/python/lancedb/table.py

@@ -337,7 +337,6 @@ class Table(ABC):
         For example, the following scan will be faster if the column ``my_col`` has
         a scalar index:
 
-        .. code-block:: python
 
             import lancedb
 
@@ -348,8 +347,6 @@ class Table(ABC):
         Scalar indices can also speed up scans containing a vector search and a
         prefilter:
 
-        .. code-block::python
-
             import lancedb
 
             db = lancedb.connect("/data/lance")
@@ -385,7 +382,6 @@ class Table(ABC):
         Examples
         --------
 
-        .. code-block:: python
 
             import lance