fix typo (#16687)

Patch from Jeff Knupp.
diff --git a/Doc/library/hashlib.rst b/Doc/library/hashlib.rst
index bc8ab2c..19d3e4c 100644
--- a/Doc/library/hashlib.rst
+++ b/Doc/library/hashlib.rst
@@ -45,7 +45,7 @@
 
 .. note::
 
-   Feeding string objects is to :meth:`update` is not supported, as hashes work
+   Feeding string objects into :meth:`update` is not supported, as hashes work
    on bytes, not on characters.
 
 .. index:: single: OpenSSL; (use in module hashlib)