[3.14] gh-136087: Remove \r from documented os.linesep values (GH-136088) (#136111)

gh-136087: Remove `\r` from documented `os.linesep` values (GH-136088)
(cherry picked from commit 980a568)

Co-authored-by: sobolevn <[email protected]>

Author: miss-islington

Lib/os.py

@@ -10,7 +10,7 @@
   - os.extsep is the extension separator (always '.')
   - os.altsep is the alternate pathname separator (None or '/')
   - os.pathsep is the component separator used in $PATH etc
-  - os.linesep is the line separator in text files ('\r' or '\n' or '\r\n')
+  - os.linesep is the line separator in text files ('\n' or '\r\n')
   - os.defpath is the default search path for executables
   - os.devnull is the file path of the null device ('/dev/null', etc.)