patch 8.2.0798: libvterm code lags behind the upstream version

Problem:    Libvterm code lags behind the upstream version.
Solution:   Include revisions 755 - 758.
diff --git a/src/libvterm/t/68screen_termprops.test b/src/libvterm/t/68screen_termprops.test
index adf7ec2..bba6660 100644
--- a/src/libvterm/t/68screen_termprops.test
+++ b/src/libvterm/t/68screen_termprops.test
@@ -14,4 +14,4 @@
 
 !Title
 PUSH "\e]2;Here is my title\a"
-  settermprop 4 "Here is my title"
+  settermprop 4 ["Here is my title"]