Update group URLs to use slugs

app/soapbox/features/groups/components/discover/group-grid-item.tsx

@@ -25,7 +25,7 @@ const GroupGridItem = forwardRef((props: IGroup, ref: React.ForwardedRef<HTMLDiv
         width,
       }}
     >
-      <Link to={`/groups/${group.id}`}>
+      <Link to={`/group/${group.slug}`}>
         <Stack
           className='aspect-h-7 aspect-w-10 h-full w-full overflow-hidden rounded-lg'
           ref={ref}

app/soapbox/features/groups/components/discover/group-list-item.tsx

@@ -21,7 +21,7 @@ const GroupListItem = (props: IGroup) => {
       alignItems='center'
       justifyContent='between'
     >
-      <Link key={group.id} to={`/groups/${group.id}`}>
+      <Link key={group.id} to={`/group/${group.slug}`}>
         <HStack alignItems='center' space={2}>
           <GroupAvatar
             group={group}