Add files not needed for installation to export ignore

We don't need these when installing the standalone globally through Composer. We just want the build, the composer.json and the license file.

Based on the [Pint configuration](https://github.com/laravel/pint/blob/main/.gitattributes)

Author: emmadesilva

.gitattributes

@@ -7,8 +7,17 @@
 *.php diff=php
 
 .github/ export-ignore
+config/ export-ignore
 tests/ export-ignore
+app/ export-ignore
 bin/ export-ignore
+
 CHANGELOG.md export-ignore
 LICENSE.md export-ignore
 SECURITY.md export-ignore
+composer.lock export-ignore
+box.json export-ignore
+phpunit.xml export-ignore
+.gitattributes export-ignore
+.gitignore export-ignore
+hyde export-ignore