fix parse boot_id error This bug was caused by an upgrade of the parse library: parse 1.19.0 Released: Jan 14, 2021. There is a "\n" at the end of contents of /proc/sys/kernel/random/boot_id. Bug: b/177880369 Test: run vts -m VtsKernelProcFileApi -t VtsKernelProcFileApi#testProcSysKernelRandomBootId Change-Id: Id0c4c0b2dd136289bfcf11e6a840d1d52253644d