fix: relation picker should not move once openened (#8026)

Fixes: #7959 

### Problem
- When searching in the dropdown, the results list would shrink based on
matching items
- This dynamic height change caused the dropdown to flip its position on
each keystroke

### Solution
- Added ```hasMinHeight``` as optional props to the
```DropdownMenuItemsContainer``` to maintain consistent height
- This prevents unwanted position recalculations and flipping while user
types
- The dropdown now stays in its initial position throughout the search
interaction

[Screencast from 2024-10-24
15-43-03.webm](https://github.com/user-attachments/assets/741317b7-fc5e-4874-8221-aa626a1a1747)

packages/twenty-front/src/modules/object-record/relation-picker/components/MultiRecordSelect.tsx

@@ -113,7 +113,7 @@ export const MultiRecordSelect = ({
           autoFocus
         />
         <DropdownMenuSeparator />
-        <DropdownMenuItemsContainer hasMaxHeight>
+        <DropdownMenuItemsContainer hasMaxHeight hasMinHeight>
           {recordMultiSelectIsLoading ? (
             <MenuItem text="Loading..." />
           ) : (