remove gb IS const

src/background.js

@@ -67,7 +67,6 @@ const {
 	CDN_BASE_URL, BROWSER_INFO, IS_CLIQZ
 } = globals;
 const IS_EDGE = (BROWSER_INFO.name === 'edge');
-const IS_GHOSTERY_BROWSER = (BROWSER_INFO.name === 'ghostery_desktop');
 const IS_FIREFOX = (BROWSER_INFO.name === 'firefox');
 const IS_ANDROID = (BROWSER_INFO.os === 'android');
 const VERSION_CHECK_URL = `${CDN_BASE_URL}/update/version`;
@@ -1656,7 +1655,7 @@ function initializeGhosteryModules() {
  */
 async function initializeSearchMessageHandler() {
 	await globals.BROWSER_INFO_READY; // ensure browser info is set
-	if (IS_GHOSTERY_BROWSER) {
+	if (BROWSER_INFO.name === 'ghostery_desktop') {
 		const sm = new SearchMessager();
 		sm.init();
 	}