src/sage/misc/sagedoc.py: Add sage_root to extlinks

Author: Matthias Koeppe

src/sage/misc/sagedoc.py

@@ -507,6 +507,7 @@ def process_dollars(s):
 extlinks = {
     'python': (f'https://docs.python.org/release/{pythonversion}/%s', None),
     'issue': ('https://github.com/sagemath/sage/issues/%s', 'Issue #%s'),
+    'sage_root': ('https://github.com/sagemath/sage/tree/develop/%s', 'SAGE_ROOT/%s'),
     'wikipedia': ('https://en.wikipedia.org/wiki/%s', 'Wikipedia article %s'),
     'arxiv': ('https://arxiv.org/abs/%s', 'arXiv %s'),
     'oeis': ('https://oeis.org/%s', 'OEIS sequence %s'),