Feature/remove dependency mui system (#331)

* Remove duplicated dependency "@mui/system"

Already included in "@mui/material"

* Remove duplicated dependency "@mui/system" - Fix theme "custom" palette

Already included in "@mui/material"

* Remove duplicated dependency "@mui/system" - Fix imports

Already included in "@mui/material"

src/components/util/StyledFab.tsx

@@ -6,8 +6,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/.
  */
 
-import { Fab } from '@mui/material';
-import { styled } from '@mui/system';
+import { Fab, styled } from '@mui/material';
 
 export const DEFAULT_FAB_STYLE = {
     position: 'fixed',