patch 8.2.3706: text property highlighting is used on Tab

Problem:    Text property highlighting is used on Tab.
Solution:   Only set in_linebreak when not on a Tab. (closes #9242)
diff --git a/src/drawline.c b/src/drawline.c
index 109b8b3..ae62be8 100644
--- a/src/drawline.c
+++ b/src/drawline.c
@@ -2046,7 +2046,7 @@
 
 		    c_extra = mb_off > 0 ? MB_FILLER_CHAR : ' ';
 		    c_final = NUL;
-		    if (n_extra > 0)
+		    if (n_extra > 0 && c != TAB)
 			in_linebreak = TRUE;
 		    if (VIM_ISWHITE(c))
 		    {