fix: add missing 'requests' when building the package with AOT (#1517)

## 📌 Description

When building flashinfer-python with AOT enabled, we need the 'requests'
package otherwise it fails with missing packages when importing modules.

## 🔍 Related Issues

Fixes #1516

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## 🧪 Tests

- [x] Tests have been added or updated as needed.
- [x] All tests are passing (`unittest`, etc.).

Signed-off-by: Emilien Macchi <[email protected]>

Author: EmilienM

custom_backend.py

@@ -8,7 +8,7 @@
 _aot_ops_dir = _root / "aot-ops"
 _aot_ops_package_dir = _root / "build" / "aot-ops-package-dir"
 
-_requires_for_aot = ["torch", "ninja", "numpy"]
+_requires_for_aot = ["torch", "ninja", "numpy", "requests"]
 
 
 def _rm_aot_ops_package_dir():