Returning CodeInfo from @generated requires explicit return

[maleadt]

Repro:

foobar(i) = i
@generated foo(i) = return first(code_lowered(foobar, Tuple{i}))
@generated bar(i) =        first(code_lowered(foobar, Tuple{i}))

foobar(42) = 42
foo(42) = 42
bar(42) = CodeInfo(:(begin
      nothing
      return i
  end))

[Keno]

#25678