In the original paper (https://arxiv.org/pdf/1812.06499.pdf), the freeze way is to freeze the whole encoder.

However, during their official implementation, the freeze way is different on the first residual block (see: https://github.com/vqdang/hover_net/blob/842964dc5d26ffe196d236d16fad16643a103850/models/hovernet/net_desc.py#L107)

We may need to adjust the freeze function to align with their implementation.

cc @KumoLiu @JHancox