Python: fix(google-ai): skip api_key check when use_vertexai is True

Author: giulio-leone

python/semantic_kernel/connectors/ai/google/google_ai/services/google_ai_chat_completion.py

@@ -119,7 +119,7 @@ def __init__(
         if not client:
             if google_ai_settings.use_vertexai and not google_ai_settings.cloud_project_id:
                 raise ServiceInitializationError("Project ID must be provided when use_vertexai is True.")
-            if not google_ai_settings.api_key:
+            if not google_ai_settings.use_vertexai and not google_ai_settings.api_key:
                 raise ServiceInitializationError("The API key is required when use_vertexai is False.")
 
         super().__init__(

python/semantic_kernel/connectors/ai/google/google_ai/services/google_ai_text_completion.py

@@ -90,7 +90,7 @@ def __init__(
         if not client:
             if google_ai_settings.use_vertexai and not google_ai_settings.cloud_project_id:
                 raise ServiceInitializationError("Project ID must be provided when use_vertexai is True.")
-            if not google_ai_settings.api_key:
+            if not google_ai_settings.use_vertexai and not google_ai_settings.api_key:
                 raise ServiceInitializationError("The API key is required when use_vertexai is False.")
 
         super().__init__(

python/semantic_kernel/connectors/ai/google/google_ai/services/google_ai_text_embedding.py

@@ -81,7 +81,7 @@ def __init__(
         if not client:
             if google_ai_settings.use_vertexai and not google_ai_settings.cloud_project_id:
                 raise ServiceInitializationError("Project ID must be provided when use_vertexai is True.")
-            if not google_ai_settings.api_key:
+            if not google_ai_settings.use_vertexai and not google_ai_settings.api_key:
                 raise ServiceInitializationError("The API key is required when use_vertexai is False.")
 
         super().__init__(