patch 8.2.0785: libvterm code lags behind the upstream version

Problem:    Libvterm code lags behind the upstream version.
Solution:   Include revisions 734 - 740.
diff --git a/src/libvterm/t/30state_pen.test b/src/libvterm/t/30state_pen.test
index 7a671e7..d1e0d14 100644
--- a/src/libvterm/t/30state_pen.test
+++ b/src/libvterm/t/30state_pen.test
@@ -28,6 +28,14 @@
   ?pen underline = 2
 PUSH "\e[24m"
   ?pen underline = 0
+PUSH "\e[4m\e[4:0m"
+  ?pen underline = 0
+PUSH "\e[4:1m"
+  ?pen underline = 1
+PUSH "\e[4:2m"
+  ?pen underline = 2
+PUSH "\e[4:3m"
+  ?pen underline = 3
 PUSH "\e[4m\e[m"
   ?pen underline = 0
 
diff --git a/src/libvterm/t/run-test.pl b/src/libvterm/t/run-test.pl
index 1b2144a..d8fbe09 100644
--- a/src/libvterm/t/run-test.pl
+++ b/src/libvterm/t/run-test.pl
@@ -177,9 +177,11 @@
 
 while( my $line = <$test> ) {
    $line =~ s/^\s+//;
-   next if $line =~ m/^(?:#|$)/;
-
    chomp $line;
+
+   next if $line =~ m/^(?:#|$)/;
+   last if $line eq "__END__";
+
    do_line( $line );
 }