docs: Add use citation from dark matter at muon colliders paper (#2341)

* Add use citation from 'Boosting dark matter searches at muon colliders
  with Machine Learning: the mono-Higgs channel as a case study'.
   - c.f. https://inspirehep.net/literature/2700441

docs/bib/use_citations.bib

@@ -1,3 +1,16 @@
+% 2023-09-20
+@article{Belfkir:2023vpo,
+    author = "Belfkir, Mohamed and Jueid, Adil and Nasri, Salah",
+    title = "{Boosting dark matter searches at muon colliders with Machine Learning: the mono-Higgs channel as a case study}",
+    eprint = "2309.11241",
+    archivePrefix = "arXiv",
+    primaryClass = "hep-ph",
+    reportNumber = "CTPU-PTC-23-37",
+    month = "9",
+    year = "2023",
+    journal = ""
+}
+
 % 2023-09-04
 @article{Fenton:2023ikr,
     author = "Fenton, Michael James and Shmakov, Alexander and Okawa, Hideki and Li, Yuji and Hsiao, Ko-Yang and Hsu, Shih-Chieh and Whiteson, Daniel and Baldi, Pierre",