Fix milestones deletion (go-gitea#25583)

Close go-gitea#25557 
Fix regression from go-gitea#25315

`data-id` is still needed for deleting milestone.

Author: HesterG

templates/repo/issue/milestones.tmpl

@@ -114,7 +114,7 @@
 								{{else}}
 									<a class="link-action flex-text-inline" href data-url="{{$.Link}}/{{.ID}}/close">{{svg "octicon-x" 14}}{{$.locale.Tr "repo.milestones.close"}}</a>
 								{{end}}
-								<a class="delete-button flex-text-inline" href="#" data-url="{{$.RepoLink}}/milestones/delete">{{svg "octicon-trash" 14}}{{$.locale.Tr "repo.issues.label_delete"}}</a>
+								<a class="delete-button flex-text-inline" href="#" data-url="{{$.RepoLink}}/milestones/delete" data-id="{{.ID}}">{{svg "octicon-trash" 14}}{{$.locale.Tr "repo.issues.label_delete"}}</a>
 							</div>
 						{{end}}
 					</div>

templates/user/dashboard/milestones.tmpl

@@ -135,7 +135,7 @@
 										{{else}}
 											<a class="link-action flex-text-inline" href data-url="{{$.Link}}/{{.ID}}/close">{{svg "octicon-x" 14}}{{$.locale.Tr "repo.milestones.close"}}</a>
 										{{end}}
-										<a class="delete-button flex-text-inline" href="#" data-url="{{$.RepoLink}}/milestones/delete">{{svg "octicon-trash" 14}}{{$.locale.Tr "repo.issues.label_delete"}}</a>
+										<a class="delete-button flex-text-inline" href="#" data-url="{{$.RepoLink}}/milestones/delete" data-id="{{.ID}}">{{svg "octicon-trash" 14}}{{$.locale.Tr "repo.issues.label_delete"}}</a>
 									</div>
 								{{end}}
 							</div>