Update docstring for Session.verify to include string support (#6859) (#6865)

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Co-authored-by: Nate Prewitt <nate.prewitt@gmail.com>

Author: M0d3v1

src/requests/sessions.py

@@ -422,6 +422,8 @@ def __init__(self):
         #: expired certificates, which will make your application vulnerable to
         #: man-in-the-middle (MitM) attacks.
         #: Only set this to `False` for testing.
+        #: If verify is set to a string, it must be the path to a CA bundle file
+        #: that will be used to verify the TLS certificate.
         self.verify = True
 
         #: SSL client certificate default, if String, path to ssl client