clean scan optimization: scan disk index only for zero lamport (#2879) #5461

Job	Run time
ios (macos-12, aarch64-apple-ios)	3m 16s
ios (macos-12, x86_64-apple-ios)	3m 36s
android (ubuntu-20.04, x86_64-linux-android)	2m 53s
ios (macos-12, aarch64-apple-darwin)	3m 26s
android (ubuntu-20.04, aarch64-linux-android)	2m 59s
ios (macos-12, x86_64-apple-darwin)	3m 38s
android (ubuntu-20.04, i686-linux-android)	2m 47s
android (ubuntu-20.04, armv7-linux-androideabi)	3m 3s
error_reporting	0s
	25m 38s

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