fix(database): create data folder if it doesn't exist

This commit adds a check to create the data folder if it doesn't already exist.
The `YamlEntityRepository` class now ensures that the data folder is created
before any data operations are performed.

Issue: #main
```

Feel free to adjust the message as needed, and don't forget to replace `#main` with the actual issue number if applicable. 😊[^1^] [^2^] [^3^]

database/src/main/java/com/georgev22/library/utilities/YamlEntityRepository.java

@@ -37,6 +37,11 @@ public YamlEntityRepository(File dataFolder, Logger logger, Class<V> entityClass
         this.dataFolder = dataFolder;
         this.logger = logger;
         this.entityClass = entityClass;
+        if (!this.dataFolder.exists()) {
+            if (this.dataFolder.mkdirs()) {
+                this.logger.log(Level.INFO, "[EntityRepository]: Created data folder: " + this.dataFolder.getAbsolutePath());
+            }
+        }
     }
 
     /**