fix duplicate keys in tables

client/src/pages/admin/competitions/CompetitionManager.tsx

@@ -316,7 +316,7 @@ const CompetitionManager: React.FC = (props: any) => {
           <TableBody>
             {competitions &&
               competitions.map((row) => (
-                <TableRow key={row.name}>
+                <TableRow key={row.id}>
                   <TableCell scope="row">
                     <Button color="primary" component={Link} to={`/editor/competition-id=${row.id}`}>
                       {row.name}

client/src/pages/admin/regions/Regions.tsx

@@ -81,7 +81,7 @@ const RegionManager: React.FC = (props: any) => {
           <TableBody>
             {cities &&
               cities.map((row) => (
-                <TableRow key={row.name}>
+                <TableRow key={row.id}>
                   <TableCell scope="row">{row.name}</TableCell>
                   <TableCell align="right">
                     <Button onClick={(event) => handleClick(event, row.id)} data-testid={row.name}>

client/src/pages/admin/users/UserManager.tsx

@@ -152,7 +152,7 @@ const UserManager: React.FC = (props: any) => {
           <TableBody>
             {users &&
               users.map((row) => (
-                <TableRow key={row.email}>
+                <TableRow key={row.id}>
                   <TableCell scope="row">{row.email}</TableCell>
                   <TableCell scope="row">{row.name}</TableCell>
                   <TableCell>{cities.find((city) => city.id === row.city_id)?.name || ''}</TableCell>