Fix #13080 - Hypernetwork/TI preview generation

Fixes sampler name reference

Same patch will be done for TI.

modules/hypernetworks/hypernetwork.py

@@ -468,7 +468,7 @@ def create_hypernetwork(name, enable_sizes, overwrite_old, layer_structure=None,
     shared.reload_hypernetworks()
 
 
-def train_hypernetwork(id_task, hypernetwork_name, learn_rate, batch_size, gradient_step, data_root, log_directory, training_width, training_height, varsize, steps, clip_grad_mode, clip_grad_value, shuffle_tags, tag_drop_out, latent_sampling_method, use_weight, create_image_every, save_hypernetwork_every, template_filename, preview_from_txt2img, preview_prompt, preview_negative_prompt, preview_steps, preview_sampler_index, preview_cfg_scale, preview_seed, preview_width, preview_height):
+def train_hypernetwork(id_task, hypernetwork_name:str, learn_rate:float, batch_size:int, gradient_step:int, data_root:str, log_directory:str, training_width:int, training_height:int, varsize:bool, steps:int, clip_grad_mode:str, clip_grad_value:float, shuffle_tags:bool, tag_drop_out:bool, latent_sampling_method:str, use_weight:bool, create_image_every:int, save_hypernetwork_every:int, template_filename:str, preview_from_txt2img:bool, preview_prompt:str, preview_negative_prompt:str, preview_steps:int, preview_sampler_name:str, preview_cfg_scale:float, preview_seed:int, preview_width:int, preview_height:int):
     from modules import images, processing
 
     save_hypernetwork_every = save_hypernetwork_every or 0
@@ -698,7 +698,7 @@ def train_hypernetwork(id_task, hypernetwork_name, learn_rate, batch_size, gradi
                         p.prompt = preview_prompt
                         p.negative_prompt = preview_negative_prompt
                         p.steps = preview_steps
-                        p.sampler_name = sd_samplers.samplers[preview_sampler_index].name
+                        p.sampler_name = sd_samplers.samplers_map[preview_sampler_name.lower()]
                         p.cfg_scale = preview_cfg_scale
                         p.seed = preview_seed
                         p.width = preview_width