docs: update Node.js runtime version

convert-action has been [updated to the node16 runtime](mheap/convert-action#3).

README.md

@@ -43,7 +43,7 @@ You can also use this action with other events - you'll just need to specify a `
 
 ## Example `package.json` for your project
 
-The two important thing you'll need to set in your action are the `main` field and the `build` script. Here's an example of a minimal `package.json` that will use `@vercel/ncc` to compile your action to `dist/index.js`, update your `action.yml` file to use the `node12` runtime and point `build-and-tag-action` at the compiled file:
+The two important thing you'll need to set in your action are the `main` field and the `build` script. Here's an example of a minimal `package.json` that will use `@vercel/ncc` to compile your action to `dist/index.js`, update your `action.yml` file to use the `node16` runtime and point `build-and-tag-action` at the compiled file:
 
 ```json
 {