make skip notice countdown customisable

src/config.ts

@@ -33,6 +33,7 @@ interface SBConfig {
     supportInvidious: boolean,
     serverAddress: string,
     minDuration: number,
+    skipNoticeDuration: number,
     audioNotificationOnSkip,
     checkForUnlistedVideos: boolean,
     testingServer: boolean,
@@ -171,6 +172,7 @@ const Config: SBObject = {
         supportInvidious: false,
         serverAddress: CompileConfig.serverAddress,
         minDuration: 0,
+        skipNoticeDuration: 4,
         audioNotificationOnSkip: false,
         checkForUnlistedVideos: false,
         testingServer: false,