Bump ExecuTorch release version to 1.4.0 (#8463)

Author: JacobSzwejbka

release/release_versions.sh

@@ -9,7 +9,7 @@ TORCHCOMMS_VERSION=${TORCHCOMMS_VERSION:-0.3.1}
 TRITON_VERSION=${TRITON_VERSION:-3.7.1}
 TORCHTEXT_VERSION=${TORCHTEXT_VERSION:-0.18.0}
 TORCHREC_VERSION=${TORCHREC_VERSION:-1.7.0}
-EXECUTORCH_VERSION=${EXECUTORCH_VERSION:-1.3.1}
+EXECUTORCH_VERSION=${EXECUTORCH_VERSION:-1.4.0}
 TORCH_TENSORRT_VERSION=${TORCH_TENSORRT_VERSION:-2.13.0}
 TORCH_TENSORRT_RTX_VERSION=${TORCH_TENSORRT_VERSION}
 TORCHAO_VERSION=${TORCHAO_VERSION:-0.18.0}