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

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

Change-Id: I0184a65eed313f8f983b554d72b8c93cf6c64d1c
Signed-off-by: Automerger Merge Worker <[email protected]>