apply a small nit

Co-authored-by: Anton <100830759+antonwolfy@users.noreply.github.com>

Author: vlad-perevezentsev

dpnp/dpnp_iface_mathematical.py

@@ -1857,7 +1857,7 @@ def ediff1d(ary, to_end=None, to_begin=None):
 Warning
 -------
 This function is deprecated. It is recommended to use
-:obj:`dpnp.trunc` instead, as it provides the same functionality of
+:func:`dpnp.trunc` instead, as it provides the same functionality of
 truncating decimal values to their integer parts.
 
 Examples