tests: cleanup test_sync_patches_pr_summary_success data

* remove: "relevant-subjects-20250610.json" as it is just a list of
  other responses
* use: shorter directory name

Signed-off-by: Ihor Solodrai <[email protected]>

Author: theihor

tests/data/test_github_sync.test_sync_patches_pr_summary_success/relevant-subjects-20250610.json

@@ -11,5 +11,9 @@
   "https://patchwork.test/api/1.1/series/?q=bpf%253A+clear+user+buf+when+bpf_d_path+failed": ["series-970926.json"],
   "https://patchwork.test/api/1.1/series/?q=bpf%253A+Fix+a+few+test+failures+with+64K+page+size": ["series-970968.json"],
   "https://patchwork.test/api/1.1/series/?q=net%253A+Fix+RCU+usage+in+task_cls_state%2528%2529+for+BPF+programs": ["series-970970.json"],
-  "https://patchwork.test/api/1.1/patches/?archived=False&delegate=121173&project=399&since=2025-06-11T00:00:00&state=1&state=13&state=15&state=2&state=5&state=7": "relevant-subjects-20250610.json"
+  "https://patchwork.test/api/1.1/patches/?archived=False&delegate=121173&project=399&since=2025-06-11T00:00:00&state=1&state=13&state=15&state=2&state=5&state=7": [
+    "patch-14114605.json",
+    "patch-14114774.json",
+    "patch-14114777.json"
+  ]
 }