docs: update CodeSandbox for issues (#2213)

* docs: update CodeSandbox for issues

* Update Feature_request.md

Author: layershifter

.github/ISSUE_TEMPLATE/Bug_report.md

@@ -20,4 +20,4 @@ x.y.z
 
 ### Testcase
 [Fork, update, and replace this sandbox to show the bug]:
-https://codesandbox.io/s/stardust-ui-example-8ismt
+https://codesandbox.io/s/fluent-ui-example-on8xf

.github/ISSUE_TEMPLATE/Feature_request.md

@@ -14,4 +14,4 @@ A clear and concise description of what you want to happen. Add any considered d
 
 ### MVP
 [Fork, update, and replace this sandbox if you can show the proposed solution]:
-https://codesandbox.io/s/stardust-ui-example-8ismt
+https://codesandbox.io/s/fluent-ui-example-on8xf