Expand regex to include `Unexpected error (ClassCastException) macroexpanding defmulti at ...`

[vemv]

(defmulti 5 class) triggers:

Unexpected error (ClassCastException) macroexpanding defmulti at (src/haystack/parser.cljc:21:1).
class java.lang.Long cannot be cast to class clojure.lang.IObj (java.lang.Long is in module java.base of loader 'bootstrap'; clojure.lang.IObj is in unnamed module of loader 'app')

...which deserves a treatment similar to that of #3506, it seems.