patch 8.1.0711: test files still use function!

Problem:    Test files still use function!.
Solution:   Remove the exclamation mark.  Fix overwriting a function.
diff --git a/src/testdir/test_number.vim b/src/testdir/test_number.vim
index 59debce..415aefc 100644
--- a/src/testdir/test_number.vim
+++ b/src/testdir/test_number.vim
@@ -2,23 +2,23 @@
 
 source view_util.vim
 
-func! s:screen_lines(start, end) abort
+func s:screen_lines(start, end) abort
   return ScreenLines([a:start, a:end], 8)
 endfunc
 
-func! s:compare_lines(expect, actual)
+func s:compare_lines(expect, actual)
   call assert_equal(a:expect, a:actual)
 endfunc
 
-func! s:test_windows(h, w) abort
+func s:test_windows(h, w) abort
   call NewWindow(a:h, a:w)
 endfunc
 
-func! s:close_windows() abort
+func s:close_windows() abort
   call CloseWindow()
 endfunc
 
-func! s:validate_cursor() abort
+func s:validate_cursor() abort
   " update skipcol.
   " wincol():
   "   f_wincol