fix(date-picker): remove border radius (#8198)

Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

Author: emyarod

packages/components/src/components/date-picker/_flatpickr.scss

@@ -21,6 +21,7 @@
   animation: none;
   direction: ltr;
   border: 0;
+  border-radius: 0;
   font-size: 14px;
   line-height: 24px;
   border-radius: 5px;