[ReleasePR redis] ARM ID Annotations for Redis (#2518)

Create to sync Azure/azure-rest-api-specs#19596
[ReCreate this PR](https://github.com/azure-resource-manager-schemas/compare/main...azure-sdk:sdkAuto/redis?expand=1)

Author: msftbot[bot]

schemas/2020-12-01/Microsoft.Cache.json

@@ -587,6 +587,7 @@
       "properties": {
         "linkedRedisCacheId": {
           "type": "string",
+          "format": "arm-id",
           "description": "Fully qualified resourceId of the linked redis cache."
         },
         "linkedRedisCacheLocation": {

schemas/2021-06-01/Microsoft.Cache.json

@@ -639,6 +639,7 @@
       "properties": {
         "linkedRedisCacheId": {
           "type": "string",
+          "format": "arm-id",
           "description": "Fully qualified resourceId of the linked redis cache."
         },
         "linkedRedisCacheLocation": {