feat: expose spectrum Flex component as wrapped deephaven component (#1869)

Simple wrapping of the flex component.

I don't see anything we need to custiomize, so just re-export it I
guess.

Author: dsmmcken

packages/components/src/spectrum/Flex.tsx

@@ -0,0 +1,5 @@
+import { Flex } from '@adobe/react-spectrum';
+
+export type { FlexProps } from '@adobe/react-spectrum';
+export { Flex };
+export default Flex;

packages/components/src/spectrum/index.ts

@@ -1,3 +1,4 @@
-export * from './picker';
+export * from './Flex';
 export * from './Item';
+export * from './picker';
 export * from './Section';