fix: ensure poster works as expected and add it to the sample (#3643)

* fix: ensure poster works as expected and add it to the sample
* chore: drop audioOnly property as not implemented on any platform
* fix(ios): do not save pause state before seeking
* fix(ts): onPlaybackRateChangeData was not correctly typed

.eslintrc

@@ -7,6 +7,9 @@
     "plugin:@typescript-eslint/eslint-recommended",
     "plugin:@typescript-eslint/recommended"
   ],
+  "rules": {
+    "no-trailing-spaces": 1
+  },
   "parserOptions": {
     "requireConfigFile": false
   }