[lldb/api] Improve error reporting in SBBreakpoint::AddName (NFCI)

This patch improves the error reporting for SBBreakpoint::AddName by
adding a new method `SBBreakpoint::AddNameWithErrorHandling` that returns
a SBError instead of a boolean.

This way, if the breakpoint naming failed in the backend, the client
(i.e. Xcode), will be able to report the reason of that failure to the
user.

rdar://64765461



Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>