fixup! Add TorStrings module for localization

replace with more common expression available in wikipedia. reported by translator dfiguera at https://hosted.weblate.org/translate/tor/tb-browseronboardingproperties/en/?checksum=91bd40ca4ab9c22f, thanks!

toolkit/torbutton/chrome/locale/en-US/browserOnboarding.properties

@@ -15,7 +15,7 @@ onboarding.tour-tor-privacy.button=Go to Tor Network
 
 onboarding.tour-tor-network=Tor Network
 onboarding.tour-tor-network.title=Travel a decentralized network.
-onboarding.tour-tor-network.description=Tor Browser connects you to the Tor network run by thousands of volunteers around the world. Unlike a VPN, there’s no one point of failure or centralized entity you need to trust in order to enjoy the internet privately.
+onboarding.tour-tor-network.description=Tor Browser connects you to the Tor network run by thousands of volunteers around the world. Unlike a VPN, there’s no single point of failure or centralized entity you need to trust in order to enjoy the internet privately.
 onboarding.tour-tor-network.description-para2=NEW: Tor Network Settings, including the ability to request bridges where Tor is blocked, can now be found in Preferences.
 onboarding.tour-tor-network.action-button=Adjust Your Tor Network Settings
 onboarding.tour-tor-network.button=Go to Circuit Display