pyright 1.1.403 started reporting "is not a known attribute of module"

Updated from `1.1.402` to `1.1.403` and started seeing `error: "CLIENT" is not a known attribute of module ".constants"`. In `pymysql`, the CLIENT constants are defined in `pymysql/constants/CLIENT.py`. I expect no error.

Reproduction repository: https://github.com/mickvangelderen/pyright-issue-10690

`main.py`
```
import pymysql.constants.CLIENT

def main():
print(f"MULTI_STATEMENTS: {pymysql.constants.CLIENT.MULTI_STATEMENTS}")

if __name__ == "__main__":
main()
```

`pyproject.toml`
```
[project]
name = "pyright-403-pymysql"
version = "0.1.0"
description = "Add your description here"
readme = "README.md"
requires-python = ">=3.12"
dependencies = [
"pymysql>=1.1.1",
]

[dependency-groups]
dev = [
"pyright>=1.1.403",
]
```

`uv run pyright`
```
/home/mick/projects/pyright-403-pymysql/main.py
/home/mick/projects/pyright-403-pymysql/main.py:4:50 - error: "CLIENT" is not a known attribute of module ".constants" (reportAttributeAccessIssue)
1 error, 0 warnings, 0 informations
```

Start with the reproduction repository's main.py and pyproject.toml, then run uv run pyright with versions 1.1.402 and 1.1.403 to compare the diagnostics. Inspect how pymysql/constants/CLIENT.py is discovered through the pymysql.constants import; done means the CLIENT.MULTI_STATEMENTS access is accepted without an error.

Written by the indexing model from the issue text.