[3.12] GH-107674: Avoid allocating boxed ints for `sys.settrace` line events (GH-107780) (#107841)

GH-107674: Avoid allocating boxed ints for `sys.settrace` line events (GH-107780)
(cherry picked from commit 37d8b904f8b5b660f556597b21c0933b841d18de)

Co-authored-by: Mark Shannon <mark@hotpy.org>