990137-Modify file streams of C# [Cross-platform] in XlsIO UG#1706

Mohan2401 merged 3 commits intohotfix/hotfix-v31.2.2syncfusion-content/document-processing-docs:hotfix/hotfix-v31.2.2from

990137-CustomXmlSupportsyncfusion-content/document-processing-docs:990137-CustomXmlSupportCopy head branch name to clipboard