fix(tornado): fix set_tag_str type error when http.route is none [bac…

…kport 2.10] (#10139)

Backport d90c31d from #10125 to 2.10.

Escalation due to trying to set route as a tag string when it is None.

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Co-authored-by: William Conti <[email protected]>

ddtrace/contrib/tornado/handlers.py

@@ -58,7 +58,8 @@ def execute(func, handler, args, kwargs):
             request_span.set_tag(ANALYTICS_SAMPLE_RATE_KEY, settings.get("analytics_sample_rate", True))
 
         http_route = _find_route(handler.application.default_router.rules, handler.request)
-        request_span.set_tag_str("http.route", http_route)
+        if http_route is not None and isinstance(http_route, str):
+            request_span.set_tag_str("http.route", http_route)
         setattr(handler.request, REQUEST_SPAN_KEY, request_span)
 
         return func(*args, **kwargs)