patch 9.1.0222: missing 'below' virt text if truncation precedes after/right text

Problem:  When a line is truncated just before 'after'/'right' virtual
          text and the line also has 'below' virtual text, then the
          'below' virtual text would not be displayed, depending on the
          order these text properties were added.
Solution: In the loop to make text properties active, skip instead of
          break for 'after'/'right' virtual text properties that are
          ignored due to truncation, so following 'below' text
          properties can still be made active.
          Similarly, a loop is needed to determine if a text property
          follows at the end of the screen. (Dylan Thacker-Smith)

related: #14307

Signed-off-by: Dylan Thacker-Smith <dylan.ah.smith@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_textprop.vim b/src/testdir/test_textprop.vim
index 22c7e46..61e5158 100644
--- a/src/testdir/test_textprop.vim
+++ b/src/testdir/test_textprop.vim
@@ -3099,6 +3099,9 @@
   call term_sendkeys(buf, ":call AddPropBelow()\<CR>")
   call VerifyScreenDump(buf, 'Test_props_with_text_truncated_just_before_after_2', {})
 
+  call term_sendkeys(buf, ":call AddPropRight()\<CR>:\<Esc>")
+  call VerifyScreenDump(buf, 'Test_props_with_text_truncated_just_before_after_2', {})
+
   call StopVimInTerminal(buf)
 endfunc