Separate the change of directory from npm/yarn commands

[Quetzacoalt91]

githubActionBuildJS/entrypoint.sh

Lines 9 to 10 in 3ac7107

	$1 --prefix $2/ install --production
	$1 --prefix $2/ run build

As you allow to use another folder by setting the path parameter, what about using this code to change directory first (https://github.com/elstudio/actions-js-build/blob/master/build/entrypoint.sh#L15-L19), then use npm install & npm run build for all cases?