Fixes #15653 -- Identity Readme issues (#15729)

Fixes missing JDK link in Identity Readme

Removes 'f' typo

sdk/identity/azure-identity/README.md

@@ -30,7 +30,7 @@ Maven dependency for Azure Secret Client library. Add it to your project's pom f
 [//]: # ({x-version-update-end})
 
 ### Prerequisites
-* [Java Development Kit (JDK)][jdk] with version 8 or above
+* A [Java Development Kit (JDK)][jdk_link], version 8 or later.
 * An [Azure subscription][azure_sub].
 * The Azure CLI can also be useful for authenticating in a development environment, creating accounts, and managing account roles.
 
@@ -357,7 +357,7 @@ Credentials can be chained together to be tried in turn until one succeeds using
 </table>
 
 Configuration is attempted in the above order. For example, if values for a client secret and certificate are both present, the client secret will be used.
-f
+
 ## Troubleshooting
 Credentials raise exceptions either when they fail to authenticate or cannot execute authentication.
 When credentials fail to authenticate, the`ClientAuthenticationException` is raised and it has a `message` attribute which
@@ -398,5 +398,6 @@ This project has adopted the [Microsoft Open Source Code of Conduct][code_of_con
 [eventhubs_client_library]: https://github.com/Azure/azure-sdk-for-java/tree/master/sdk/eventhubs/azure-messaging-eventhubs
 [azure_core_library]: https://github.com/Azure/azure-sdk-for-java/tree/master/sdk/core
 [javadoc]: http://azure.github.io/azure-sdk-for-java
+[jdk_link]: https://docs.microsoft.com/java/azure/jdk/?view=azure-java-stable
 
 ![Impressions](https://azure-sdk-impressions.azurewebsites.net/api/impressions/azure-sdk-for-java%2Fsdk%2Fidentity%2Fazure-identity%2FREADME.png)