Fix BC-FIPS artifactID

Author: SalusaSecondus

README.md

@@ -22,7 +22,7 @@ To use this SDK you must have:
   Or, you can pick it up from Maven (groupId: `org.bouncycastle`, artifactId: `bcprov-ext-jdk15on`).
 
   As of version 1.6.1,
-  the AWS Encryption SDK will also work with Bouncy Castle FIPS (groupId: `org.bouncycastle`, artifactId: `bcprov-ext-jdk15on`).
+  the AWS Encryption SDK will also work with Bouncy Castle FIPS (groupId: `org.bouncycastle`, artifactId: `bc-fips`).
   Please follow Bouncy Castle's FIPS [documentation](https://www.bouncycastle.org/documentation.html),
   including User Guides and Security Policy for proper installation and configuration.