training stuck at initialisation

Nobody has claimed this yet.

### Bug description

trainining stucked with following log

```
[rank: 0] Seed set to 42
Initializing distributed: GLOBAL_RANK: 0, MEMBER: 1/5
```

### What version are you seeing the problem on?

master

### How to reproduce the bug

_No response_

### Error messages and logs

```
# [rank: 0] Seed set to 42
# Initializing distributed: GLOBAL_RANK: 0, MEMBER: 1/5
```

### Environment

Current environment

```
#- Lightning Component (e.g. Trainer, LightningModule, LightningApp, LightningWork, LightningFlow):
#- PyTorch Lightning Version (e.g., 1.5.0):
#- Lightning App Version (e.g., 0.5.2):
#- PyTorch Version (e.g., 2.0):
#- Python version (e.g., 3.9):
#- OS (e.g., Linux):
#- CUDA/cuDNN version:
#- GPU models and configuration:
#- How you installed Lightning(`conda`, `pip`, source):
#- Running environment of LightningApp (e.g. local, cloud):
```

### More info

_No response_

cc @justusschock

Start by collecting the missing environment details and an exact reproduction for the reported distributed initialization log. Then trace the training startup path that emits "Initializing distributed" and determine why execution remains at member 1/5. Done means the cause is reproduced and documented with a verified fix or a clearly actionable diagnosis.

Written by the indexing model from the issue text.