Upgrade Gradle Tools to >= 4.1.2 + Gradle Wrapper >= 6.5.1 (Linux issue)

[Gustl22]

Plz upgrade the gradle version of the projects in order to work properly on all platforms:

No toolchains found in the NDK toolchains folder for ABI with prefix: arm-linux-androideabi

Related: https://github.com/flutter/flutter/issues/53657#issuecomment-795808016

build.gradle:

dependencies {
    classpath 'com.android.tools.build:gradle:4.1.3'
}

gradle-wrapper.properties:

distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip

[domesticmouse]

Which sample is this for?

[Gustl22]

I suspect this affects all samples with these specs: https://github.com/search?q=repo%3Aflutter%2Fsamples%20services.gradle.org%2Fdistributions%2Fgradle&type=code

https://github.com/search?q=repo%3Aflutter%2Fsamples+%22com.android.tools.build%3Agradle%22&type=code

But I think I originally tested it with the platform_channel sample, where the according versions have been updated in #1022