New bulk select header overflows when the window is too small to display the whole table header
### Expected Behavior

_No response_

### Actual Behaviour

![image](https://github.com/kestra-io/kestra/assets/37618489/4336be2d-69bc-4e27-85a8-b8598461fab0)


### Steps To Reproduce

_No response_

### Environment Information

- Kestra Version:
- Operating System (OS / Docker / Kubernetes):
- Java Version (If not docker):


### Example flow

_No response_
ui/src/components/layout/SelectTable.vue
ui/src/components/layout/SelectTable.vue
diff --git a/ui/src/components/layout/SelectTable.vue b/ui/src/components/layout/SelectTable.vue
index efa3a9cec3..d505ff72b6 100644
--- a/ui/src/components/layout/SelectTable.vue
+++ b/ui/src/components/layout/SelectTable.vue
@@ -11,9 +11,9 @@
                 this.$emit("selection-change", selection);
             },
             computeHeaderSize() {
-                const tableHead = this.$refs.table.$el.querySelector('thead');
-                this.$el.style.setProperty("--table-header-width", `${tableHead.clientWidth}px`);
-                this.$el.style.setProperty("--table-header-height", `${tableHead.clientHeight}px`);
+                const tableElement = this.$refs.table.$el;
+                this.$el.style.setProperty("--table-header-width", `${tableElement.clientWidth}px`);
+                this.$el.style.setProperty("--table-header-height", `${tableElement.querySelector('thead').clientHeight}px`);
             }
         },
         props: {
