docs(tempfile): correct Windows temp directory search order

The existing docs claim gettempdir() searches C:\TEMP, C:\TMP, \TEMP, \TMP
on Windows, but the actual implementation (Lib/tempfile.py lines 192-194)
first checks TMPDIR, TEMP, and TMP environment variables.

On Windows, TEMP and TMP typically point to:
- %USERPROFILE%\AppData\Local\Temp (user temp)
- %SYSTEMROOT%\Temp (system temp)

Update the docs to reflect the actual search order: env vars first, then
hardcoded fallback paths.

Fixes #151138

Author: Diwak4r

Doc/library/tempfile.rst

@@ -348,8 +348,9 @@ The module defines the following user-callable items:
 
    #. A platform-specific location:
 
-      * On Windows, the directories :file:`C:\\TEMP`, :file:`C:\\TMP`,
-        :file:`\\TEMP`, and :file:`\\TMP`, in that order.
+      * On Windows, the directories :file:`{USERPROFILE}\\AppData\\Local\\Temp`,
+        :file:`{SYSTEMROOT}\\Temp`, :file:`c:\\temp`, :file:`c:\\tmp`,
+        :file:`\\temp`, and :file:`\\tmp`, in that order.
 
       * On all other platforms, the directories :file:`/tmp`, :file:`/var/tmp`, and
         :file:`/usr/tmp`, in that order.