[runner]: Tighten HTTPS check. (#8016)

I forgot that `.` has meaning in regex. Whoops!
diff --git a/tools/runner/runner.js b/tools/runner/runner.js
index c17c01f..ef0b6a4 100644
--- a/tools/runner/runner.js
+++ b/tools/runner/runner.js
@@ -833,7 +833,7 @@
 
     load: function(path) {
         this.ensure_test_window();
-        if (path.match(".https."))
+        if (path.match(/\.https\./))
           this.test_window.location.href = this.https_server + path;
         else
           this.test_window.location.href = this.server + path;