Fix project_encoder

vit_gpt2/modeling_flax_gpt2.py

@@ -312,7 +312,8 @@ class FlaxGPT2Block(nn.Module):
             # [IMPORTANT] Cross attention requires ``causal=False``! This is a bug I made previously.
             self.cross_attn = FlaxGPT2Attention(config=self.config, dtype=self.dtype, causal=False, self_attn=False)
 
-            if self.config.project_encoder:
+            project_encoder = getattr(self.config, "project_encoder", None)
+            if project_encoder:
                 self.encoder_projection_ln = nn.LayerNorm(epsilon=self.config.layer_norm_epsilon, dtype=self.dtype)
                 self.encoder_projection_mlp = FlaxGPT2MLP(self.config, self.config.hidden_size, dtype=self.dtype)
 
@@ -352,7 +353,8 @@ class FlaxGPT2Block(nn.Module):
         cross_attn_weights = None
         if encoder_hidden_states is not None:
 
-            if self.config.project_encoder:
+            project_encoder = getattr(self.config, "project_encoder", None)
+            if project_encoder:
                 residual = encoder_hidden_states
                 encoder_hidden_states = self.encoder_projection_ln(encoder_hidden_states)
                 feed_forward_hidden_states = self.encoder_projection_mlp(