Don't pass `false` query value for `enableCI`

`?enableCI=false` in the main window URL is treated as truthy value so
don't pass it at all.

main.js

@@ -224,7 +224,7 @@ function prepareURL(pathSegments, moreKeys) {
       cdnUrl2: config.get('cdn').get('2'),
       certificateAuthority: config.get('certificateAuthority'),
       environment: enableCI ? 'production' : config.environment,
-      enableCI,
+      enableCI: enableCI ? true : undefined,
       node_version: process.versions.node,
       hostname: os.hostname(),
       appInstance: process.env.NODE_APP_INSTANCE,

preload.js

@@ -518,10 +518,12 @@ try {
     getRegionCode: () => window.storage.get('regionCode'),
     logger: window.log,
   });
-  window.CI = config.enableCI && {
-    setProvisioningURL: url => ipc.send('set-provisioning-url', url),
-    deviceName: title,
-  };
+  window.CI = config.enableCI
+    ? {
+        setProvisioningURL: url => ipc.send('set-provisioning-url', url),
+        deviceName: title,
+      }
+    : undefined;
 
   // these need access to window.Signal:
   require('./ts/models/messages');