chore(composer): Clean up composer.json and add composer.lock for dotCMS PHP example

- Removed unnecessary repositories section from composer.json.
- Added composer.lock file to lock dependencies for the dotCMS PHP example.

Author: fmontes

examples/dotcms-php/composer.json

@@ -2,12 +2,6 @@
     "name": "dotcms/php-example",
     "description": "Example of using dotCMS PHP SDK",
     "type": "project",
-    "repositories": [
-        {
-            "type": "path",
-            "url": "../../"
-        }
-    ],
     "require": {
         "php": "^8.2",
         "dotcms/php-sdk": "^1.0.0"