mass replace "flip map -> forEach"

See `forEach`-introduction commit.
```
rg 'flip map ' --files-with-matches | xargs sed -i 's/flip map /forEach /g'
```

1 files changed, 1 insertions, 1 deletions

diff --git a/nixos/modules/system/boot/loader/grub/grub.nix b/nixos/modules/system/boot/loader/grub/grub.nix
index 4e4d14985b0d..eca9dad64222 100644
--- a/nixos/modules/system/boot/loader/grub/grub.nix
+++ b/nixos/modules/system/boot/loader/grub/grub.nix
@@ -684,7 +684,7 @@ in
           assertion = if args.efiSysMountPoint == null then true else hasPrefix "/" args.efiSysMountPoint;
           message = "EFI paths must be absolute, not ${args.efiSysMountPoint}";
         }
-      ] ++ flip map args.devices (device: {
+      ] ++ forEach args.devices (device: {
         assertion = device == "nodev" || hasPrefix "/" device;
         message = "GRUB devices must be absolute paths, not ${device} in ${args.path}";
       }));