docs(README.md): add note about MacOS potentially requiring 'sudo' when installing package globally

The README.md file now includes a note that MacOS may prompt the user to run the 'npm install -g opencommit' command with 'sudo' when installing the package globally. This note is added to provide clarity and help users who encounter this situation.

Author: di-sukharev

README.md

@@ -29,6 +29,8 @@ You can use OpenCommit by simply running it via the CLI like this `oco`. 2 secon
    npm install -g opencommit
    ```
 
+   MacOS may ask to run the command with `sudo` when installing a package globally.
+
 2. Get your API key from [OpenAI](https://platform.openai.com/account/api-keys). Make sure that you add your payment details, so the API works.
 
 3. Set the key to OpenCommit config: