add twinbert tri letter config

twinbert/mainstream/twinbert_tri_letter_config.json

@@ -0,0 +1,12 @@
+{
+  "attention_probs_dropout_prob": 0.1,
+  "hidden_act": "gelu",
+  "hidden_dropout_prob": 0.1,
+  "hidden_size": 512,
+  "initializer_range": 0.02,
+  "intermediate_size": 512,
+  "max_position_embeddings": 33,
+  "num_attention_heads": 8,
+  "num_hidden_layers": 6,
+  "vocab_size": 49293
+}