Update rc.yml to support variable in Windows CMD

Author: testforstephen

.azure-pipelines/rc.yml

@@ -52,7 +52,7 @@ extends:
               - task: CmdLine@2
                 displayName: Replace AI Key
                 inputs:
-                  script: npx [email protected] -I -f package.json -e "this.aiKey=\"$AI_KEY\""
+                  script: npx [email protected] -I -f package.json -e "this.aiKey=\"%AI_KEY%\""
               - task: CmdLine@2
                 displayName: VSCE package
                 inputs: