Fix android compilation warnings

[jeluard]

User Story

As a developer, I don't want warnings when running commands.

Description

Type: Bug

Running react-native run-android generates a bunch of warnings. We want to remove as much as possible.

Examples of warnings:

Configuration 'compile' in project ':app' is deprecated. Use 'implementation' instead.
registerResGeneratingTask is deprecated, use registerGeneratedFolders(FileCollection)
registerResGeneratingTask is deprecated, use registerGeneratedFolders(FileCollection)

Configuration 'compile' in project ':react-native-splash-screen' is deprecated. Use 'implementation' instead.
Configuration 'testCompile' in project ':react-native-splash-screen' is deprecated. Use 'testImplementation' instead.
WARNING: The specified Android SDK Build Tools version (25.0.3) is ignored, as it is below the minimum supported version (26.0.2) for Android Gradle Plugin 3.0.1.
Android SDK Build Tools 26.0.2 will be used.
To suppress this warning, remove "buildToolsVersion '25.0.3'" from your build.gradle file, as each version of the Android Gradle Plugin now has a default version of the build tools.

/home/julien/Documents/Projects/status-react/android/app/src/main/AndroidManifest.xml:23:5-87 Warning:
        uses-permission#android.permission.BLUETOOTH was tagged at AndroidManifest.xml:23 to remove other declarations but no other declaration present
/home/julien/Documents/Projects/status-react/android/app/src/main/AndroidManifest.xml:25:5-92 Warning:
        uses-permission#android.permission.WRITE_CONTACTS was tagged at AndroidManifest.xml:25 to remove other declarations but no other declaration present
/home/julien/Documents/Projects/status-react/android/app/src/main/AndroidManifest.xml:28:5-90 Warning:
        uses-permission#android.permission.RECORD_VIDEO was tagged at AndroidManifest.xml:28 to remove other declarations but no other declaration present

> Task :app:hemroidBuild
/home/julien/Android/Sdk/ndk-bundle/build/core/setup-app.mk:81: Android NDK: Application targets deprecated ABI(s): mips64 armeabi mips    
/home/julien/Android/Sdk/ndk-bundle/build/core/setup-app.mk:82: Android NDK: Support for these ABIs will be removed in a future NDK release.  

Some might be related to our dependencies: in this case we must create issues in relevant project if needed.

[status-open-bounty]

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Paid to: pacamara
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[pacamara]

@jeluard Have pushed a fix which removes nearly all the warnings, and explains what/why for the remaining ones: #3086