MDL-75738 tool_moodlenet: Upgrade clean user profile slow, pointless

There is an upgrade to clean the moodlenetprofile field which
performs very poorly, but it is also not needed because an upgrade
further down sets this field to empty string anyway.

admin/tool/moodlenet/db/upgrade.php

@@ -105,24 +105,6 @@ function xmldb_tool_moodlenet_upgrade(int $oldversion) {
     // Automatically generated Moodle v3.9.0 release upgrade line.
     // Put any upgrade step following this.
 
-    if ($oldversion < 2021052501) {
-
-        // Find out if there are users with MoodleNet profiles set.
-        $sql = "SELECT u.*
-                  FROM {user} u
-                 WHERE u.moodlenetprofile IS NOT NULL";
-
-        $records = $DB->get_records_sql($sql);
-
-        foreach ($records as $record) {
-            // Force clean user value just incase there is something malicious.
-            $record->moodlenetprofile = clean_text($record->moodlenetprofile, PARAM_NOTAGS);
-            $DB->update_record('user', $record);
-        }
-
-        upgrade_plugin_savepoint(true, 2021052501, 'tool', 'moodlenet');
-    }
-
     if ($oldversion < 2022021600) {
         // This is a special case for if MoodleNet integration has never been enabled,
         // or if defaultmoodlenet is not set for whatever reason.