docs: update bigframes.pandas.Index docstrings (#1144)

* docs: update `bigframes.pandas.Index` docstrings

* updating more methods

* update docstrings of more methods

* update docstrings

* update docs

* update docstrings

* fix failing doc test

* fix docs indentation

* fix indentation error

* fix doctest error

* fix doctest error

* fix errors

* fix errors

* fix failing doctest

* remove .name docstring

Author: arwas11

bigframes/core/indexes/base.py

@@ -134,7 +134,6 @@ def name(self, value: blocks.Label):
 
     @property
     def names(self) -> typing.Sequence[blocks.Label]:
-        """Returns the names of the Index."""
         return self._block._index_labels
 
     @names.setter
@@ -175,7 +174,6 @@ def dtypes(self) -> pandas.Series:
 
     @property
     def size(self) -> int:
-        """Returns the size of the Index."""
         return self.shape[0]
 
     @property
@@ -186,12 +184,6 @@ def empty(self) -> bool:
     @property
     @validations.requires_ordering()
     def is_monotonic_increasing(self) -> bool:
-        """
-        Return a boolean if the values are equal or increasing.
-
-        Returns:
-            bool
-        """
         return typing.cast(
             bool,
             self._block.is_monotonic_increasing(self._block.index_columns),