With OS X 13 and/or Xcode 14, Sage can produce warnings

ld: warning: dylib (/path/to/SAGE_ROOT/local/lib/libec.dylib) was built for newer macOS version (13.0) than being linked (12.3)

Let's filter these out when doctesting.

Component: doctest framework

Author: John Palmieri

Branch/Commit: bcab6e5

Reviewer: Kwankyu Lee

Issue created by migration from https://trac.sagemath.org/ticket/34741