Assert existence of arch-specific Android prebuilt when auto-linking

[kraenhansen]

When we're auto-linking prebuilds for Android, we have an opportunity fail early by passing the arch(s) being built and fail if a specific prebuilt binary is missing.

If we're not failing and the binary is missing, it will simply fail to load at runtime instead.

Somewhere around here:

react-native-node-api/packages/host/android/build.gradle

Lines 136 to 149 in 5c67f90

	task linkNodeApiModules {
	doLast {
	exec {
	// TODO: Support --strip-path-suffix
	commandLine 'npx', 'react-native-node-api', 'link', '--android', rootProject.rootDir.absolutePath
	standardOutput = System.out
	errorOutput = System.err
	// Enable color output
	environment "FORCE_COLOR", "1"
	}
	android.sourceSets.main.jniLibs.srcDirs += file("../auto-linked/android").listFiles()
	}
	}