Add ml.p5e.48xlarge to EFA instance lists in sagemaker-train and sagemaker-core

# Add ml.p5e.48xlarge to EFA instance lists in sagemaker-train and sagemaker-core

## Description

The `SM_EFA_NCCL_INSTANCES` and `SM_EFA_RDMA_INSTANCES` lists in the sagemaker-python-sdk are missing `ml.p5e.48xlarge`, causing NCCL hangs during distributed training initialization on P5e instances when using the SDK's container drivers.

Additionally, `ml.p5.48xlarge` is missing from `SM_EFA_RDMA_INSTANCES` (it's only in `SM_EFA_NCCL_INSTANCES`).

## Current State

```python
SM_EFA_NCCL_INSTANCES = [
"ml.g4dn.8xlarge",
"ml.g4dn.12xlarge",
"ml.g5.48xlarge",
"ml.p3dn.24xlarge",
"ml.p4d.24xlarge",
"ml.p4de.24xlarge",
"ml.p5.48xlarge",
"ml.trn1.32xlarge",
]

SM_EFA_RDMA_INSTANCES = [
"ml.p4d.24xlarge",
"ml.p4de.24xlarge",
"ml.trn1.32xlarge",
]
```

## Expected State

```python
SM_EFA_NCCL_INSTANCES = [
"ml.g4dn.8xlarge",
"ml.g4dn.12xlarge",
"ml.g5.48xlarge",
"ml.p3dn.24xlarge",
"ml.p4d.24xlarge",
"ml.p4de.24xlarge",
"ml.p5.48xlarge",
"ml.p5e.48xlarge", # ADD
"ml.trn1.32xlarge",
]

SM_EFA_RDMA_INSTANCES = [
"ml.p4d.24xlarge",
"ml.p4de.24xlarge",
"ml.p5.48xlarge", # ADD
"ml.p5e.48xlarge", # ADD
"ml.trn1.32xlarge",
]
```

## Impact

Without these entries, the SDK's container drivers don't set the required EFA environment variables (`FI_PROVIDER=efa`, `FI_EFA_USE_DEVICE_RDMA=1`, `RDMAV_FORK_SAFE=1`) for P5e instances, causing NCCL to hang during collective initialization in multi-node distributed training.

## Related

- sagemaker-training-toolkit issue: https://github.com/aws/sagemaker-training-toolkit/issues/240
- sagemaker-training-toolkit PR: https://github.com/aws/sagemaker-training-toolkit/pull/241
- P5e instances use EFA with RDMA support, same as P4d/P4de/P5

## Questions

1. Is there a specific process for testing EFA/instance-specific changes on actual hardware before merging?
2. Should integration tests be added for P5e EFA configuration, or are unit tests sufficient?

Start by locating the SM_EFA_NCCL_INSTANCES and SM_EFA_RDMA_INSTANCES definitions in the sagemaker-train and sagemaker-core components. Compare both lists with the expected state in this issue, then check the relevant unit-test coverage; done means both P5 instances are represented in the appropriate EFA lists.

Written by the indexing model from the issue text.