Update GraphRAG version

[ekzhu]

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Issue body

GraphRAG made some API changes since 1.2.0. We need to catch up with the latest version.

Also update the autogen version in the sample: https://github.com/microsoft/autogen/blob/main/python/samples/agentchat_graphrag/requirements.txt

Related: #6201

[lspinheiro]

I will try to have a look soon.

[cuckootan]

"run Autogen and GraphRAG sample, report error: ModuleNotFoundError: No module named 'graphrag.config.config_file_loader'" the issue still exist after upgrading GraphRAG version. Details:
#6201 (comment)

[cv-marvin]

same issue from 0.6.1 to GraphRAG 2.0 above

python -c "from autogen_ext.tools.graphrag import GlobalSearchTool, LocalSearchTool; print('Impor
t successful')"

Traceback (most recent call last):
File "", line 1, in
File "python3.12/site-packages/autogen_ext/tools/graphrag/init.py", line 9, in
from ._global_search import GlobalSearchTool, GlobalSearchToolArgs, GlobalSearchToolReturn
File "python3.12/site-packages/autogen_ext/tools/graphrag/_global_search.py", line 8, in
from graphrag.config.config_file_loader import load_config_from_file
ModuleNotFoundError: No module named 'graphrag.config.config_file_loader