Write a Python function `find_min_length_sublist(lst)` that takes a list of lists `lst` as input and returns the sublist with the minimum length. If there are multiple sublists with the same minimum length, return the first one encountered.
#### Example Usage
```python [main.nopy]
print(find_min_length_sublist([[1], [1, 2], [1, 2, 3]])) # Output: [1]
print(find_min_length_sublist([[1, 1], [1, 1, 1], [1, 2, 7, 8]])) # Output: [1, 1]
print(find_min_length_sublist([['x'], ['x', 'y'], ['x', 'y', 'z']])) # Output: ['x']
```
#### Constraints
- The input list will contain at least one sublist.
- Each sublist will have a non-negative length.