Clarify Android ABI filtering guidance

[danyalahmed1995]

Description of what this PR is changing or adding, and why:

Updates the Android ABI filtering guidance to clarify when -Pdisable-abi-filtering=true is required.

The docs now distinguish between ABI filters configured in defaultConfig, which can be preserved automatically, and ABI filters configured under buildTypes or productFlavors, which require disabling Flutter's default ABI filtering.

Issues fixed by this PR (if any):

Clarifies guidance discussed in flutter/flutter#188009.

PRs or commits this PR depends on (if any):

Related to flutter/flutter#177753 and flutter/flutter#181828.

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[gemini-code-assist]

Code Review

This pull request updates the documentation regarding Android ABI filtering in Flutter, advising developers to configure abiFilters in defaultConfig rather than buildTypes or productFlavors, and updating the flag usage to -Pdisable-abi-filtering=true. The feedback suggests using a nested ndk block in the Kotlin DSL code example to make it more idiomatic and readable.

[parlough]

/gcbrun

[flutter-website-bot]

Staged preview of the updated docs.flutter.dev site (updated for commit 8ebd714):

https://flutter-docs-prod--docs-pr13514-docs-android-abi-filte-s2iuoknx.web.app

[flutter-website-bot]

Staged preview of the updated flutter.dev site (updated for commit 8ebd714):

https://flutter-dev-230821--www-pr13514-docs-android-abi-filte-2yvdpns8.web.app

[sfshaza2]

lgtm.