Change memory option from '6 GB' to '8 GB'

Typo from initial deployment caught in workshop testing

Author: greg-the-coder

templates/awshp-k8s-rag-with-claude-code/main.tf

@@ -54,8 +54,8 @@ data "coder_parameter" "memory" {
     value = "4"
   }
   option {
-    name  = "6 GB"
-    value = "6"
+    name  = "8 GB"
+    value = "8"
   }
 }