1020121 - FAQ - Update the queries regarding DocIO library in UG

[GOPINATH-SF4767]

FAQ's:

1. Is font substitution supported for DOCX-to-DOCX operations in DocIO?
2. How can I retrieve all merge fields in a Word document using DocIO library?
3. Why is memory not cleared after completing the conversion process in ASP NET Core Web Application using DocIO?
4. Why "This file format is not supported" exception thrown while trying to opening a .doc file using DocIO library?

[SyncfusionBuild]

Build Status: INQUEUE 🕒
Build Location: 1020121-FAQ-HF

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Build Status: INPROGRESS 🔃
Build Location: 1020121-FAQ-HF

[SyncfusionBuild]

CI Status: SUCCESS ✅
Source Compilation: SUCCESS ✅
Build Location: 1020121-FAQ-HF
Technical Error(s): 0
Spelling Error(s): 0
Image Alt Text Error(s): 0
Image Size Error(s): 0
Image Name Error(s): 0
Front matter Error(s): 0
File Path Error(s): 0
CodeSnippet File Path Missing Error(s): 0
Toc Anchor Tags Validation Error(s): 0
MD Tag Validation Error(s): 0