[example] integrate seq-parallel tutorial with CI (#2463)

examples/tutorial/sequence_parallel/config.py

@@ -1,11 +1,8 @@
 from colossalai.amp import AMP_TYPE
 
-DATA_PATH = ''
-VOCAB_FILE_PATH = ''
-
 # hyper-parameters
-TRAIN_ITERS = 1000000
-DECAY_ITERS = 990000
+TRAIN_ITERS = 10
+DECAY_ITERS = 4
 WARMUP_FRACTION = 0.01
 GLOBAL_BATCH_SIZE = 32    # dp world size * sentences per GPU
 EVAL_ITERS = 10
@@ -13,12 +10,12 @@ EVAL_INTERVAL = 10
 LR = 0.0001
 MIN_LR = 1e-05
 WEIGHT_DECAY = 0.01
-SEQ_LENGTH = 512
+SEQ_LENGTH = 128
 
 # BERT config
-DEPTH = 12
-NUM_ATTENTION_HEADS = 12
-HIDDEN_SIZE = 768
+DEPTH = 4
+NUM_ATTENTION_HEADS = 4
+HIDDEN_SIZE = 128
 
 # model config
 ADD_BINARY_HEAD = False