[build] enable existing pytorch (for GH200, aarch64, nightly) (#8713)

use_existing_torch.py

@@ -0,0 +1,18 @@
+import glob
+
+requires_files = glob.glob('requirements*.txt')
+requires_files += ["pyproject.toml"]
+for file in requires_files:
+    print(f">>> cleaning {file}")
+    with open(file, 'r') as f:
+        lines = f.readlines()
+    if "torch" in "".join(lines).lower():
+        print("removed:")
+        with open(file, 'w') as f:
+            for line in lines:
+                if 'torch' not in line.lower():
+                    f.write(line)
+                else:
+                    print(line.strip())
+    print(f"<<< done cleaning {file}")
+    print()