RUM-872 Keep Secured Text Hidden

[maxep]

What and why?

UITextInputTraits's isSecureTextEntry and textContentType properties are mutable, meaning that a sensitive texts could be revealed to the end user. e.g.: Revealing a password for verification.

But in Session Replay, we should keep considering the text as sensitive even if it was revealed.

How?

Keep sensitivity in memory using associated object on views conforming to UITextInputTraits.

Review checklist

• [x] Feature or bugfix MUST have appropriate tests (unit, integration)
• [x] Make sure each commit and the PR mention the Issue number or JIRA reference
• [x] Add CHANGELOG entry for user facing changes

[datadog-datadog-prod-us1[bot]]

Datadog Report

Branch report: maxep/RUM-872/keep-secure-fields-hidden Commit report: cba150d Test service: dd-sdk-ios

:white_check_mark: 0 Failed, 3470 Passed, 0 Skipped, 2m 18.44s Total Time :small_red_triangle_down: Test Sessions change in coverage: 3 decreased, 4 increased, 7 no change

:small_red_triangle_down: Code Coverage Decreases vs Default Branch (3)

• test DatadogSessionReplayTests iOS 30.57% (-0.06%) - Details
• test DatadogInternalTests iOS 79.48% (-0.05%) - Details
• test DatadogCoreTests iOS 72.69% (-0.01%) - Details