Fix and narrow terms for better scoping

[cpholguera]

Description

This pull request updates test and demo documentation to clarify terminology around logging sensitive data, replacing generic terms like "secrets" and "sensitive data" with more precise language such as "authenticators" and "user sensitive data." The changes aim to improve clarity and consistency across Android and iOS test cases and demos.

Android Documentation Updates:

• Updated MASTG-DEMO-0006.md to use "authenticators" (e.g., API keys) instead of "secrets" in both the title and description, and clarified evaluation instructions accordingly. [1] [2]
• Revised MASTG-TEST-0203.md and MASTG-TEST-0231.md test titles, descriptions, and evaluation criteria to consistently use "user sensitive data" instead of just "sensitive data." [1] [2] [3] [4] [5]

iOS Documentation Updates:

• Changed the title and evaluation steps in MASTG-TEST-0296.md to refer specifically to "user sensitive data" and updated the corresponding demo title in MASTG-DEMO-0066.md to focus on authenticators. [1] [2] [3] [4]

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