There is no point in setting:

$upgraderunning = 0;

In the code below:

https://github.com/moodle/moodle/blob/269a8a8a1b3965e95e713ccc93ad1b7eb0d0e249/lib/upgradelib.php#L292
if (!$upgraderunning) {
   if (CLI_SCRIPT) {
  // never stop CLI upgrades
  $upgraderunning = 0;
} else {
  // web upgrade not running or aborted  throw new moodle_exception('upgradetimedout', 'admin', "$CFG>wwwroot/$CFG>admin/");
  }
}
 

As $upgraderunning is then not used for anything that setting it to 0 would influence.

The code above would be equivalent to:

if (!$upgraderunning && !CLI_SCRIPT)

{             // web upgrade not running or aborted             throw new \moodle_exception('upgradetimedout', 'admin', "$CFG->wwwroot/$CFG->admin/"); }

 

I also have some doubts about the logic here - when would the above condition (when $upgraderunning is false) trigger?