trace-ir.hpp: pass `UuidView` object to `CommonTrace::uuid()` method

trace-ir.hpp: pass `UuidView` object to `CommonTrace::uuid()` method

To simplify the code, the ctf::ir::TraceCls returns a Uuid, so accepting
a UuidView here makes it trivial to pass the return of one to the other.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Change-Id: I1f7a8fa51d932d764d77cd8dafe087cbf89f77b7
Reviewed-on: https://review.lttng.org/c/babeltrace/+/8188
Reviewed-by: Philippe Proulx <eeppeliteloop@gmail.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/10831
CI-Build: Philippe Proulx <eeppeliteloop@gmail.com>
Tested-by: jenkins <jenkins@lttng.org>