Laravel with wordpress app Build failed

Deployed a Laravel template app. Then on my local machine added wordpress in public/blog directory and tested successfully. Committed the changes & pushed to the github repo. But the build failed with the below error -

Using Nixpacks
context: 9763c96a9fde44e77334d03d44215ba2
Nixpacks build failed

Error: Error reading public/blog/wp-includes/js/tw-sack.js

Caused by:
stream did not contain valid UTF-8

project id - 9fcbfd19-f603-4be4-b71b-5a6b5e03f511

service id - 5c7b0674-53f1-4909-87f6-e1b6cb9b815e
make sure files are encoded with utf-8
How can I encode files with utf-8?
usually you can set your text editor / ide to save in utf-8 encoding