Update build_ios.md

doc/build_ios.md

@@ -159,6 +159,6 @@ xcodebuild -exportArchive -archivePath $PWD/build/Cesium.xcarchive -exportOption
 /Applications/Xcode.app/Contents/Applications/Application\ Loader.app/Contents/Frameworks/ITunesSoftwareService.framework/Support/altool --upload-app -f $PWD/build/Cesium.ipa -u YOUR_APPLE_ID
 ```
 
-The prompt for your password, if you use two-factor authentication, you'll need to generate an application specific password for this command (see: https://appleid.apple.com/account/manage)
+The command will prompt for your password, if you use two-factor authentication, you'll need to generate an application specific password for this command (see: https://appleid.apple.com/account/manage)
 
 5. Go to `https://appstoreconnect.apple.com/`, then `My Apps` and publish your App from there.
\ No newline at end of file