Fix typo

Oauth -> OAuth

Author: changeworld

articles/api-management/howto-protect-backend-frontend-azure-ad-b2c.md

@@ -62,7 +62,7 @@ Here's a quick overview of the steps:
 1. Build the Function API
 1. Configure the Function API to enable EasyAuth with the new Azure AD B2C Client IDs and Keys and lock down to APIM VIP
 1. Build the API Definition in API Management
-1. Set up Oauth2 for the API Management API configuration
+1. Set up OAuth2 for the API Management API configuration
 1. Set up the **CORS** policy and add the **validate-jwt** policy to validate the OAuth token for every incoming request
 1. Build the calling application to consume the API
 1. Upload the JS SPA Sample
@@ -221,7 +221,7 @@ You'll need to add CIDR formatted blocks of addresses to the IP restrictions pan
 1. Click Browse, choose the function app you're hosting the API inside, and click select. Next, click select again.
 1. Give the API a name and description for API Management's internal use and add it to the ‘unlimited’ Product.
 1. Copy and record the API's 'base URL' and click 'create'.
-1. Click the 'settings' tab, then under subscription - switch off the 'Subscription Required' checkbox as we'll use the Oauth JWT token in this case to rate limit. Note that if you're using the consumption tier, this would still be required in a production environment.
+1. Click the 'settings' tab, then under subscription - switch off the 'Subscription Required' checkbox as we'll use the OAuth JWT token in this case to rate limit. Note that if you're using the consumption tier, this would still be required in a production environment.
 
    > [!TIP]
    > If using the consumption tier of APIM the unlimited product won't be available as an out of the box. Instead, navigate to "Products" under "APIs" and hit "Add".