Upgrade rust/crates/gdbstub to 0.6.3 am: f15aee5b6c am: 2a1488b2c7 am: f03fa684f6 am: 9d394b410b am: 3ae72c2317

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/gdbstub/+/2191020

Change-Id: I73d8a8f7874ef4279738f756c5fc3b24d0e375b5
Signed-off-by: Automerger Merge Worker <[email protected]>