dev_urls: Make requests to /docs redirect to the index.

This makes it easier to browse to the docs in development mode, and
more closely matches ReadTheDocs production.

zerver/lib/test_helpers.py

@@ -505,6 +505,7 @@ def write_instrumentation_reports(full_suite: bool, include_webhooks: bool) -> N
             "config-error/(?P<error_name>[^/]+)",
             "confirmation_key/",
             "node-coverage/(?P<path>.+)",
+            "docs/",
             "docs/(?P<path>.+)",
             "casper/(?P<path>.+)",
             "static/(?P<path>.+)",

zproject/dev_urls.py

@@ -7,7 +7,7 @@ from django.contrib.staticfiles.views import serve as staticfiles_serve
 from django.http.request import HttpRequest
 from django.http.response import FileResponse
 from django.urls import path
-from django.views.generic import TemplateView
+from django.views.generic import RedirectView, TemplateView
 from django.views.static import serve
 
 from zerver.views.auth import login_page
@@ -52,6 +52,7 @@ urls = [
             "show_indexes": True,
         },
     ),
+    path("docs/", RedirectView.as_view(url="/docs/index.html")),
     path(
         "docs/<path:path>",
         serve,