fix: allow payload scrubbing override

[pauldambra]

We don't allow someone to override our header scrubbing. That's fine because we're concrete about what we detect and remove.

We also don't allow someone to override our payload scubbing, but that's purposefully leaning towards false positives over false negatives. So, we can redact content that isn't actually private. Great for safety but not usability.

This changes so that the network mask function replaces the scrubPayload function (as requested by a customer)

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I considered double opt-in e.g. requiring config.maskFnOverridesDefaultScrubbing = true but that felt too much on top of a dialog in the app and having to provide a masking function

[github-actions]

Size Change: -76 B (0%)

Total Size: 941 kB

Filename	Size	Change
dist/array.full.js	224 kB	-19 B (0%)
dist/array.js	124 kB	-19 B (0%)
dist/es.js	124 kB	-19 B (0%)
dist/module.js	124 kB	-19 B (0%)

ℹ️ View Unchanged

Filename	Size
dist/exception-autocapture.js	12.1 kB
dist/recorder-v2.js	106 kB
dist/recorder.js	106 kB
dist/surveys-module-previews.js	62 kB
dist/surveys.js	58.3 kB

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