Minor comment update in copilotchat appsetting comments (microsoft#775)

### Motivation and Context
Be consistent with examples in comments

### Description
Minor comment update in copilotchat appsetting comments

samples/apps/copilot-chat-app/webapi/appsettings.json

@@ -24,15 +24,15 @@
   // Completions are used for generating AI responses from the user's input.
   // https://platform.openai.com/docs/guides/chat
   // To use Azure OpenAI as the AI completion service:
-  //  - Set AIService to "AzureOpenAI"
-  //  - Set DeploymentOrModelId to the name of the deployment to use (e.g., "gpt-35-turbo", "gpt-4", etc.)
-  //  - Set Endpoint to the endpoint of your Azure OpenAI instance (e.g., "https://contoso.openai.azure.com")
-  //  - Set Key using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Completion:Key" "MY_AZURE_OPENAI_KEY")
+  //  - Set "AIService" to "AzureOpenAI"
+  //  - Set "DeploymentOrModelId" to the name of the deployment to use (e.g., "gpt-35-turbo", "gpt-4", etc.)
+  //  - Set "Endpoint" to the endpoint of your Azure OpenAI instance (e.g., "https://contoso.openai.azure.com")
+  //  - Set "Key" using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Completion:Key" "MY_AZURE_OPENAI_KEY")
   // 
   // To use OpenAI as the AI completion service:
-  //  - Set AIService to "OpenAI"
-  //  - Set DeploymentOrModelId to the name of the deployment to use (e.g., "gpt-3.5-turbo", "gpt-4", etc.)
-  //  - Set Key using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Completion:Key" "MY_OPENAI")
+  //  - Set "AIService" to "OpenAI"
+  //  - Set "DeploymentOrModelId" to the name of the deployment to use (e.g., "gpt-3.5-turbo", "gpt-4", etc.)
+  //  - Set "Key" using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Completion:Key" "MY_OPENAI_KEY")
   //
   "Completion": {
     "Label": "Completion",
@@ -46,15 +46,15 @@
   // Embeddings are used for semantically encoding memories.
   // https://platform.openai.com/docs/guides/embeddings
   // To use Azure OpenAI as the AI embedding service:
-  //  - Set AIService" to "AzureOpenAI"
-  //  - Set DeploymentOrModelId" to the name of the deployment to use (e.g., "text-embedding-ada-002")
-  //  - Set Endpoint" to the endpoint of your Azure OpenAI instance (e.g., "https://contoso.openai.azure.com")
-  //  - Set Key using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Embedding:Key" "MY_AZURE_OPENAI_KEY")
+  //  - Set "AIService" to "AzureOpenAI"
+  //  - Set "DeploymentOrModelId" to the name of the deployment to use (e.g., "text-embedding-ada-002")
+  //  - Set "Endpoint" to the endpoint of your Azure OpenAI instance (e.g., "https://contoso.openai.azure.com")
+  //  - Set "Key" using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Embedding:Key" "MY_AZURE_OPENAI_KEY")
   // 
   // To use OpenAI as the AI embedding service:
-  //  - Set AIService to "OpenAI"
-  //  - Set DeploymentOrModelId to the name of the deployment to use (e.g., "text-embedding-ada-002" )
-  //  - Set Key using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Embedding:Key" "MY_OPENAI")
+  //  - Set "AIService" to "OpenAI"
+  //  - Set "DeploymentOrModelId" to the name of the deployment to use (e.g., "text-embedding-ada-002" )
+  //  - Set "Key" using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Embedding:Key" "MY_OPENAI_KEY")
   //
   "Embedding": {
     "Label": "Embeddings",
@@ -144,15 +144,15 @@
   // - Set Enabled to false to disable the planner which can save a round-trip to the AI service but will disable plug-in support.
   //
   // To use Azure OpenAI with the planner:
-  //  - Set AIService" to "AzureOpenAI"
-  //  - Set DeploymentOrModelId" to the name of the deployment to use (e.g., "gpt-35-turbo")
-  //  - Set Endpoint" to the endpoint of your Azure OpenAI instance (e.g., "https://contoso.openai.azure.com")
-  //  - Set Key using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Planner:AIService:Key" "MY_AZURE_OPENAI_KEY")
+  //  - Set "AIService" to "AzureOpenAI"
+  //  - Set "DeploymentOrModelId" to the name of the deployment to use (e.g., "gpt-35-turbo")
+  //  - Set "Endpoint" to the endpoint of your Azure OpenAI instance (e.g., "https://contoso.openai.azure.com")
+  //  - Set "Key" using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Planner:AIService:Key" "MY_AZURE_OPENAI_KEY")
   //
   // To use OpenAI with the planner:
-  //  - Set AIService to "OpenAI"
-  //  - Set DeploymentOrModelId to the name of the deployment to use (e.g., "gpt-3.5-turbo" )
-  //  - Set Key using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Planner:AIService:Key" "MY_OPENAI")
+  //  - Set "AIService" to "OpenAI"
+  //  - Set "DeploymentOrModelId" to the name of the deployment to use (e.g., "gpt-3.5-turbo" )
+  //  - Set "Key" using dotnet's user secrets (see above) (i.e. dotnet user-secrets set "Planner:AIService:Key" "MY_OPENAI_KEY")
   //
   "Planner": {
     "Enabled": true,