Support data asset input

[chenslucky]

Description

In local mode, we first attempt to use the configured document_nodes_file if it's valid, otherwise, we fall back to documents_folder. In cloud mode, document_nodes_file is used if configured, without any validity checks because we cannot check if it is a data asset. For cloud mode, both local files and data assets can be used.

Local Tests:

1. happy path

   • skip split
     

   • has split:
     documents_folder = "..\..\docs\reference\tools-reference"
     

2. invalid file path and folder path
   

Cloud Tests:

1. happy path (local and asset)

   • local path
     skip split: https://ml.azure.com/runs/tough_guava_3znwhjb9sc?wsid=/subscriptions/96aede12-2f73-41cb-b983-6d11a904839b/resourcegroups/promptflow/workspaces/yaopfeus&tid=72f988bf-86f1-41af-91ab-2d7cd011db47
     has split: https://ml.azure.com/runs/happy_flower_kr0y3yy56z?wsid=/subscriptions/96aede12-2f73-41cb-b983-6d11a904839b/resourcegroups/promptflow/workspaces/yaopfeus&tid=72f988bf-86f1-41af-91ab-2d7cd011db47
   • data asset path
     skip split: https://ml.azure.com/runs/frosty_raisin_tsrhm41knv?wsid=/subscriptions/96aede12-2f73-41cb-b983-6d11a904839b/resourcegroups/promptflow/workspaces/yaopfeus&tid=72f988bf-86f1-41af-91ab-2d7cd011db47
     has split: https://ml.azure.com/runs/neat_engine_stv9pnc0tg?wsid=/subscriptions/96aede12-2f73-41cb-b983-6d11a904839b/resourcegroups/promptflow/workspaces/yaopfeus&tid=72f988bf-86f1-41af-91ab-2d7cd011db47

2. invalid local file path and folder path

   • invalid path but not default path
     
   • default path
     

3. invalid data asset path
   https://ml.azure.com/runs/lucid_brake_dvwr49x28v?wsid=/subscriptions/96aede12-2f73-41cb-b983-6d11a904839b/resourcegroups/promptflow/workspaces/yaopfeus&tid=72f988bf-86f1-41af-91ab-2d7cd011db47#
   

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Testing Guidelines

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