Revert "Revert "Make outout of cppbor::parse safely mutable"" am: 1398a70364 am: 5a54201c94

Original change: https://android-review.googlesource.com/c/platform/system/libcppbor/+/2474924

Change-Id: I9f965b0dabe445244ad812787a712467fc14549d
Signed-off-by: Automerger Merge Worker <[email protected]>