Fix function call line split in debug.jl

Fix unnecessarily split function call in DomainError hint registration.
Line length reduced to 123 characters, improving readability.

Following Catalyst.jl PR #1306 guidelines.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: claude

src/debug.jl

@@ -58,10 +58,7 @@ expression. Two common reasons for this issue are:
 
 function __init__()
     Base.Experimental.register_error_hint(DomainError) do io, e
-        if e isa DomainError &&
-           occursin(
-            "will only return a complex result if called with a complex argument. Try ",
-            e.msg)
+        if e isa DomainError && occursin("will only return a complex result if called with a complex argument. Try ", e.msg)
             println(io, DOMAINERROR_COMPLEX_MSG)
         end
     end