patch 8.2.0706: Vim9: using assert_fails() causes function to finish

Problem:    Vim9: using assert_fails() causes function to finish.
Solution:   Check did_emsg instead of called_emsg.
diff --git a/src/testdir/test_vim9_disassemble.vim b/src/testdir/test_vim9_disassemble.vim
index 1170341..5c4ecd2 100644
--- a/src/testdir/test_vim9_disassemble.vim
+++ b/src/testdir/test_vim9_disassemble.vim
@@ -17,6 +17,7 @@
   buffers
   echo arg
   echo local
+  echo &lines
   echo v:version
   echo s:scriptvar
   echo g:globalvar
@@ -42,6 +43,7 @@
         ' EXEC \+buffers.*' ..
         ' LOAD arg\[-1\].*' ..
         ' LOAD $0.*' ..
+        ' LOADOPT &lines.*' ..
         ' LOADV v:version.*' ..
         ' LOADS s:scriptvar from .*test_vim9_disassemble.vim.*' ..
         ' LOADG g:globalvar.*' ..