Reset issue boards add issues modal page when filtering

The page param is reset when filtering or when opening, previously it was possible to get the page param stuck on a high number making it impossible to either filter or to close & open the modal and get the issues you want to see.

Closes #29616

app/assets/javascripts/boards/components/modal/index.js

@@ -64,6 +64,7 @@ require('./empty_state');
       },
       filter: {
         handler() {
+          this.page = 1;
           this.loadIssues(true);
         },
         deep: true,
@@ -115,6 +116,9 @@ require('./empty_state');
         return this.activeTab === 'selected' && this.selectedIssues.length === 0;
       },
     },
+    created() {
+      this.page = 1;
+    },
     components: {
       'modal-header': gl.issueBoards.ModalHeader,
       'modal-list': gl.issueBoards.ModalList,