MINOR: [Dev][Archery] Reinstate version constraint on setuptools_scm for comment bot (#40162)

The comment bot depends on an internal setuptools_scm API that was changed in setuptools_scm 8.
We therefore need to reinstate the Archery version constraint that was removed in #40150

See example failure at https://github.com/apache/arrow/actions/runs/7976567301/job/21777437575

Authored-by: Antoine Pitrou <antoine@python.org>
Signed-off-by: Antoine Pitrou <antoine@python.org>

Author: pitrou

dev/archery/setup.py

@@ -30,7 +30,7 @@
 extras = {
     'benchmark': ['pandas'],
     'crossbow': ['github3.py', jinja_req, 'pygit2>=1.6.0', 'requests',
-                 'ruamel.yaml', 'setuptools_scm'],
+                 'ruamel.yaml', 'setuptools_scm<8.0.0'],
     'crossbow-upload': ['github3.py', jinja_req, 'ruamel.yaml',
                         'setuptools_scm'],
     'docker': ['ruamel.yaml', 'python-dotenv'],