A basic CLAUDE.md based on bad things I see claude code doing (#162163)

Signed-off-by: Edward Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/162163
Approved by: https://github.com/albanD, https://github.com/Skylion007

CLAUDE.md

@@ -0,0 +1,15 @@
+# Testing
+
+Use our test class and test runner:
+
+```
+from torch.testing._internal.common_utils import run_tests, TestCase
+
+class TestFeature(TestCase):
+    ...
+
+if __name__ == "__main__":
+    run_tests()
+```
+
+To test Tensor equality, use assertEqual.