[UT][v0.18.0] Fix APC nightly UT and TTFT ratio (cherry-pick #7468) (#8053)

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Cherry-pick from https://github.com/vllm-project/vllm-ascend/pull/7468

- Fix TTFT ratio threshold from 0.8 to 0.4 for prefix cache benchmarks
- Fix max_out_len values for warm_up and benchmark configs
- Applied to both DeepSeek-R1-0528-W8A8 and Qwen3-32B-Int8 configs

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Signed-off-by: underfituu <hzhucong@163.com>

tests/e2e/nightly/single_node/models/configs/Prefix-Cache-DeepSeek-R1-0528-W8A8.yaml

@@ -42,7 +42,7 @@ test_cases:
       - metric: "TTFT"
         baseline: "prefix0"
         target: "prefix75"
-        ratio: 0.8
+        ratio: 0.4
         operator: "<"
     benchmarks:
       warm_up:
@@ -51,7 +51,7 @@ test_cases:
         request_conf: vllm_api_stream_chat
         dataset_conf: gsm8k/gsm8k_gen_0_shot_cot_str_perf
         num_prompts: 210
-        max_out_len: 2
+        max_out_len: 1
         batch_size: 1000
         baseline: 0
         threshold: 0.97
@@ -61,7 +61,7 @@ test_cases:
         request_conf: vllm_api_stream_chat
         dataset_conf: gsm8k/gsm8k_gen_0_shot_cot_str_perf
         num_prompts: 210
-        max_out_len: 1500
+        max_out_len: 1
         batch_size: 18
         baseline: 1
         threshold: 0.97
@@ -71,7 +71,7 @@ test_cases:
         request_conf: vllm_api_stream_chat
         dataset_conf: gsm8k/gsm8k_gen_0_shot_cot_str_perf
         num_prompts: 210
-        max_out_len: 1500
+        max_out_len: 1
         batch_size: 18
         baseline: 1
         threshold: 0.97

tests/e2e/nightly/single_node/models/configs/Prefix-Cache-Qwen3-32B-Int8.yaml

@@ -35,7 +35,7 @@ test_cases:
       - metric: "TTFT"
         baseline: "prefix0"
         target: "prefix75"
-        ratio: 0.8
+        ratio: 0.4
         operator: "<"
     benchmarks:
       warm_up:
@@ -44,7 +44,7 @@ test_cases:
         request_conf: vllm_api_stream_chat
         dataset_conf: gsm8k/gsm8k_gen_0_shot_cot_str_perf
         num_prompts: 210
-        max_out_len: 2
+        max_out_len: 1
         batch_size: 1000
         baseline: 0
         threshold: 0.97
@@ -54,7 +54,7 @@ test_cases:
         request_conf: vllm_api_stream_chat
         dataset_conf: gsm8k/gsm8k_gen_0_shot_cot_str_perf
         num_prompts: 210
-        max_out_len: 1500
+        max_out_len: 1
         batch_size: 48
         baseline: 1
         threshold: 0.97
@@ -64,7 +64,7 @@ test_cases:
         request_conf: vllm_api_stream_chat
         dataset_conf: gsm8k/gsm8k_gen_0_shot_cot_str_perf
         num_prompts: 210
-        max_out_len: 1500
+        max_out_len: 1
         batch_size: 48
         baseline: 1
         threshold: 0.97