[RANTS-68] fix: z-index for image picker popover button (change project cover) (#6812)

Author: prateekshourya29

web/core/components/core/image-picker-popover.tsx

@@ -149,7 +149,7 @@ export const ImagePickerPopover: React.FC<Props> = observer((props) => {
   useOutsideClickDetector(ref, handleClose);
 
   return (
-    <Popover className="relative z-20" ref={ref} tabIndex={tabIndex} onKeyDown={handleKeyDown}>
+    <Popover className="relative z-19" ref={ref} tabIndex={tabIndex} onKeyDown={handleKeyDown}>
       <Popover.Button
         className="rounded border border-custom-border-300 bg-custom-background-100 px-2 py-1 text-xs text-custom-text-200 hover:text-custom-text-100"
         onClick={handleOnClick}