Update these URLs and embeds to the TS tags/branches

Author: timdorr

docs/tutorials/essentials/part-3-data-flow.md

@@ -45,7 +45,7 @@ To get started, you can open and fork this CodeSandbox:
 
 <iframe
   class="codesandbox"
-  src="https://codesandbox.io/embed/github/reduxjs/redux-essentials-example-app/tree/433b1132560f07c5911432182b6a4047610c25e9/?&fontsize=14&hidenavigation=1&theme=dark&runonclick=1"
+  src="https://codesandbox.io/embed/github/reduxjs/redux-essentials-example-app/tree/ts-checkpoint-0-setup/?&fontsize=14&hidenavigation=1&theme=dark&runonclick=1"
   title="redux-essentials-example-app"
   allow="geolocation; microphone; camera; midi; vr; accelerometer; gyroscope; payment; ambient-light-sensor; encrypted-media; usb"
   sandbox="allow-modals allow-forms allow-popups allow-scripts allow-same-origin"

docs/tutorials/essentials/part-4-using-data.md

@@ -32,7 +32,7 @@ Now that you know the core steps to write Redux logic, we're going to use those
 
 :::info
 
-As a reminder, the code examples focus on the key concepts and changes for each section. See the CodeSandbox projects and the [`tutorial-steps` branch in the project repo](https://github.com/reduxjs/redux-essentials-example-app/tree/tutorial-steps) for the complete changes in the application.
+As a reminder, the code examples focus on the key concepts and changes for each section. See the CodeSandbox projects and the [`tutorial-steps-ts` branch in the project repo](https://github.com/reduxjs/redux-essentials-example-app/tree/tutorial-steps-ts) for the complete changes in the application.
 
 :::
 

docs/tutorials/essentials/part-5-async-logic.md

@@ -51,7 +51,7 @@ Also, the mock server has been set up to reuse the same random seed each time th
 
 :::info
 
-As a reminder, the code examples focus on the key concepts and changes for each section. See the CodeSandbox projects and the [`tutorial-steps` branch in the project repo](https://github.com/reduxjs/redux-essentials-example-app/tree/tutorial-steps) for the complete changes in the application.
+As a reminder, the code examples focus on the key concepts and changes for each section. See the CodeSandbox projects and the [`tutorial-steps-ts` branch in the project repo](https://github.com/reduxjs/redux-essentials-example-app/tree/tutorial-steps-ts) for the complete changes in the application.
 
 :::
 
@@ -1031,7 +1031,6 @@ const postsSlice = createSlice({
 // Remove `postAdded`
 export const { postUpdated, reactionAdded } = postsSlice.actions
 // highlight-end
-
 ```
 
 ### Checking Thunk Results in Components