try some more linkcheck options (#2010)

Author: zingale

Docs/source/conf.py

@@ -226,10 +226,22 @@ def get_version():
 linkcheck_retries = 3
 linkcheck_timeout = 100
 linkcheck_allow_unauthorized = True
+linkcheck_workers = 5
+linkcheck_rate_limit_timeout = 60
+
+user_agent = "Mozilla/5.0 (X11; Linux x86_64; rv:120.0) Gecko/20100101 Firefox/120.0"
+linkcheck_request_headers = {
+    "*": {
+        "User-Agent": (
+            "Mozilla/5.0 (X11; Linux x86_64; rv:120.0) "
+            "Gecko/20100101 Firefox/120.0"
+        )
+    }
+}
 linkcheck_ignore = [r"https://doi.org/10.1103/[Pp]hys[Rr]ev*",
-                    "https://www.sciencedirect.com/science/article/pii/S016892741200133X"]
-user_agent = "Mozilla/5.0 (X11; Linux x86_64; rv:25.0) Gecko/20100101 Firefox/25.0"
-
+                    "https://www.sciencedirect.com/science/article/pii/S016892741200133X",
+                    "https://doi.org/10.1145/641876.641877",
+                    "https://doi.org/10.1137/S1064827597326651"]
 
 # -- Options for Texinfo output -------------------------------------------