docs: Update documentation that became obsolete due to code cleanup

Author: Dannyj1

src/main/java/nl/dannyj/mistral/interceptors/MistralHeaderInterceptor.java

@@ -30,7 +30,7 @@ public class MistralHeaderInterceptor implements Interceptor {
 
     public MistralHeaderInterceptor(@NonNull String apiKey) {
         if (apiKey.isBlank()) {
-            throw new IllegalArgumentException("No API key provided in MistralClient");
+            throw new IllegalArgumentException("No API key provided");
         }
 
         this.apiKey = apiKey;

src/main/java/nl/dannyj/mistral/services/HttpService.java

@@ -39,7 +39,7 @@ public class HttpService {
     private final OkHttpClient httpClient;
 
     /**
-     * Constructor that initializes the HttpService with a provided MistralClient.
+     * Constructor that initializes the HttpService with a provided OkHttpClient.
      *
      * @param httpClient The OkHttpClient to be used for making requests to the Mistral AI API
      */

src/main/java/nl/dannyj/mistral/services/MistralService.java

@@ -58,7 +58,7 @@ public class MistralService {
     private final Validator validator;
 
     /**
-     * Constructor that initializes the MistralService with a provided MistralClient and HttpService.
+     * Constructor that initializes the MistralService with a provided HttpService and ObjectMapper.
      *
      * @param httpService The HttpService to be used for making HTTP requests to the Mistral AI API
      * @param objectMapper The ObjectMapper to be used for converting objects to and from JSON