Generate groups and reorders imports incorrectly

gqlgen version: v0.17.66
go version: 1.23.3

full repro: https://github.com/mdakovac/gqlgen-import-sorting/tree/main

Go lets you group imports by separating them with a newline, however when you run the `generate` command, this grouping is broken.

import statement before `generate` in `graph/schema.resolvers.go` file
```
import (
"context"
"fmt"

"github.com/rs/zerolog"

"github.com/example/gqlgen-import-sorting/graph/model"
"github.com/spf13/viper"
)
```

after `generate`
```
import (
"context"
"fmt"

"github.com/example/gqlgen-import-sorting/graph/model"
"github.com/rs/zerolog"
"github.com/spf13/viper"
)
```