patch 8.2.2100: insufficient testing for function range and dict

Problem:    Insufficient testing for function range and dict.
Solution:   Add a few tests. (Dominique Pellé, closes #7428)
diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index d6e408a..dd4429e 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -2099,6 +2099,7 @@
   let mydict = {'data': [0, 1, 2, 3], 'len': function("Mylen")}
   eval mydict.len->call([], mydict)->assert_equal(4)
   call assert_fails("call call('Mylen', [], 0)", 'E715:')
+  call assert_fails('call foo', 'E107:')
 endfunc
 
 func Test_char2nr()