batch['text'] adds [self.mapping_task[task_name]] twice

[lighten001]

function log_images will call get_input (which is the second time be called) on train batch end

z, c = self.get_input(batch, self.first_stage_key, bs=N)

so batch['text'] will add [self.mapping_task[task_name]] twice

batch['txt'] = batch['txt'] + [self.mapping_task[task_name]]

the c_task should be c_all[BS:BS+1,:1,:] to avoid the two same task prompt

[salesforce-cla]

Thanks for the contribution! Before we can merge this, we need @lighten001 to sign the Salesforce Inc. Contributor License Agreement.