Fix: Embedder source should be openAi, not openai (#3150)

Author: Rijoanul-Shanto

learn/ai_powered_search/getting_started_with_ai_search.mdx

@@ -48,7 +48,7 @@ Add a new `source` field to your embedder object:
 ```json
 {
   "products-openai": {
-    "source": "openai"
+    "source": "openAi"
   }
 }
 ```
@@ -64,7 +64,7 @@ Add a new `model` field to your embedder object:
 ```json
 {
   "products-openai": {
-    "source": "openai",
+    "source": "openAi",
     "model": "text-embedding-3-small"
   }
 }
@@ -81,7 +81,7 @@ Add the `apiKey` field to your embedder:
 ```json
 {
   "products-openai": {
-    "source": "openai",
+    "source": "openAi",
     "model": "text-embedding-3-small",
     "apiKey": "OPEN_AI_API_KEY",
   }
@@ -103,7 +103,7 @@ A good template should be short and only include the most important information
 ```json
 {
   "products-openai": {
-    "source": "openai",
+    "source": "openAi",
     "model": "text-embedding-3-small",
     "apiKey": "OPEN_AI_API_KEY",
     "documentTemplate": "An object used in a kitchen named '{{doc.name}}'"