Add speedometer benchmark suite

Author: jacob-hughes

softdev.bib

@@ -3003,3 +3003,11 @@ @misc{chromium20cssbug
     year = {2020},
     author = {Google},
 }
+
+@misc{speedometer,
+    title = {Speedometer2.1 benchmark suite},
+    howpublished = {\url{https://browserbench.org/Speedometer2.1/}},
+    note = {Accessed: 2023-03-02},
+    year = {2022},
+    author = {WebKit},
+}