docs: update heroku config vars image

Author: DenverCoder1

README.md

@@ -143,7 +143,7 @@ You can deploy the PHP files on any website server with PHP installed or as a He
   4. Scroll to the bottom and click **"Generate token"**
   5. **Add the token** as a Config Var with the key `TOKEN` and your username with the key `USERNAME`:
 
-  ![image](https://user-images.githubusercontent.com/20955511/128092565-937c3df0-6087-40b5-bec7-2744a3467680.png)
+  ![heroku config variables](https://user-images.githubusercontent.com/20955511/136054776-fffb1b11-1765-490c-9fb4-43758e371ccc.png)
 
   6. Click **"Deploy App"** at the end of the form
   7. Once the app is deployed, you can use `<your-app-name>.herokuapp.com` in place of `github-readme-streak-stats.herokuapp.com`
@@ -169,7 +169,7 @@ You can deploy the PHP files on any website server with PHP installed or as a He
   6. Scroll to the bottom and click **"Generate token"**
   7. **Add the token** to the environment variables with the label `TOKEN` and your username as `USERNAME`, then click Save.
 
-  ![image](https://user-images.githubusercontent.com/20955511/119418221-2b5b8580-bd00-11eb-8d4b-05e98c74c0e1.png)
+  ![zeet config variables](https://user-images.githubusercontent.com/20955511/119418221-2b5b8580-bd00-11eb-8d4b-05e98c74c0e1.png)
 
   8. Click the **Deployments** tab to find the URL you will use in place of `github-readme-streak-stats.herokuapp.com`