Remove insensitive terms from repo: migrate from "master" to "main"

[jbadan]

Description

master -> main per new SAP open source guidelines. Deadline 12/31.

• update CI, scripts and repo
• master must not be present in the source code at all - don't just rename the branch
• audit for other insensitive terms (I did a brief look and I think master is our only one we need to change)

For more info, see email sent 10/5 from Open Source Program Office

Versions

fundamental-react: n/a

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