patch 8.2.0999: moving to next sentence gets stuck on quote

Problem:    Moving to next sentence gets stuck on quote.
Solution:   When moving to the next sentence doesn't result in moving, advance
            a character and try again. (closes #6291)
diff --git a/src/testdir/test_textobjects.vim b/src/testdir/test_textobjects.vim
index eed84e3..6eb6fbb 100644
--- a/src/testdir/test_textobjects.vim
+++ b/src/testdir/test_textobjects.vim
@@ -311,6 +311,17 @@
   normal! 17|yas
   call assert_equal("A '([sentence.])'  ", @")
 
+  " don't get stuck on a quote at the start of a sentence
+  %delete _
+  call setline(1, ['A sentence.', '"A sentence"?', 'A sentence!'])
+  normal gg))
+  call assert_equal(3, getcurpos()[1])
+
+  %delete _
+  call setline(1, ['A sentence.', "'A sentence'?", 'A sentence!'])
+  normal gg))
+  call assert_equal(3, getcurpos()[1])
+
   %delete _
 endfunc