added simple tests

Author: artemnefedov

src/main/java/io/github/artemnefedov/javaai/service/impl/OpenAIImplementation.java

@@ -46,10 +46,14 @@
 @Setter
 public class OpenAIImplementation implements OpenAI {
 
-    private String baseURL = Config.getInstance().getProperties("url.openai.base");
-    private String compURL = baseURL + Config.getInstance().getProperties("url.openai.completions");
-    private String imgBuilderURL = baseURL + Config.getInstance().getProperties("url.openai.image_generator");
-    private String chatURL = baseURL + Config.getInstance().getProperties("url.openai.chat");
+    private String baseURL = Config.getInstance()
+            .getProperties("url.openai.base");
+    private String compURL = baseURL + Config.getInstance()
+            .getProperties("url.openai.completions");
+    private String imgBuilderURL = baseURL + Config.getInstance()
+            .getProperties("url.openai.image_generator");
+    private String chatURL = baseURL + Config.getInstance()
+            .getProperties("url.openai.chat");