fix: update link to DA diagram (#27)

Author: piyush117

ibm_catalog.json

@@ -113,7 +113,7 @@
               {
                 "diagram": {
                   "caption": "Catalog management",
-                  "url": "https://raw.githubusercontent.com/terraform-ibm-modules/terraform-ibm-catalog-management/main/reference-architecture/catalog.svg",
+                  "url": "https://raw.githubusercontent.com/terraform-ibm-modules/terraform-ibm-catalog-management/main/reference-architectures/catalog.svg",
                   "type": "image/svg+xml"
                 },
                 "description": "This architecture supports creating an an IBM Cloud catalog"
@@ -264,7 +264,7 @@
               {
                 "diagram": {
                   "caption": "Catalog VPE object",
-                  "url": "https://raw.githubusercontent.com/terraform-ibm-modules/terraform-ibm-catalog-management/main/reference-architecture/vpe.svg",
+                  "url": "https://raw.githubusercontent.com/terraform-ibm-modules/terraform-ibm-catalog-management/main/reference-architectures/vpe.svg",
                   "type": "image/svg+xml"
                 },
                 "description": "This architecture supports creating an an IBM Cloud catalog VPE object"

reference-architecture/catalog.svg renamed to reference-architectures/catalog.svg

@@ -4,4 +4,4 @@ This solution supports provisioning and configuring an IBM Cloud catalog.
 
 :exclamation: **Important:** This solution is not intended to be called by other modules because it contains a provider configuration and is not compatible with the `for_each`, `count`, and `depends_on` arguments. For more information, see [Providers Within Modules](https://developer.hashicorp.com/terraform/language/modules/develop/providers).
 
-![catalog](../../reference-architecture/catalog.svg)
+![catalog](../../reference-architectures/catalog.svg)

reference-architecture/vpe.svg renamed to reference-architectures/vpe.svg

@@ -4,4 +4,4 @@ This solution supports provisioning and configuring an IBM Cloud catalog VPE obj
 
 :exclamation: **Important:** This solution is not intended to be called by other modules because it contains a provider configuration and is not compatible with the `for_each`, `count`, and `depends_on` arguments. For more information, see [Providers Within Modules](https://developer.hashicorp.com/terraform/language/modules/develop/providers).
 
-![vpe](../../reference-architecture/vpe.svg)
+![vpe](../../reference-architectures/vpe.svg)