remove auto-sys-last-traceback functionality

[cjdoris]

Addresses part of #402.

[github-actions]

Benchmark Results (Julia v1)

Time benchmarks

	main	e855ca6...	main / e855ca6...
basic/@py/pydict/init	0.257 ± 0.058 ms	0.257 ± 0.043 ms	1 ± 0.28
basic/@py/pydict/pydel	0.261 ± 0.027 ms	0.26 ± 0.034 ms	1 ± 0.17
basic/julia/pydict/init	0.232 ± 0.072 ms	0.237 ± 0.081 ms	0.981 ± 0.45
basic/julia/pydict/pydel	0.237 ± 0.038 ms	0.24 ± 0.056 ms	0.986 ± 0.28
gc/full	0.671 ± 0.0095 s	0.475 ± 0.0056 s	1.41 ± 0.026
time_to_load	2.26 ± 0.021 s	2.3 ± 0.022 s	0.982 ± 0.013

Memory benchmarks

	main	e855ca6...	main / e855ca6...
basic/@py/pydict/init	5.01 k allocs: 0.0764 MB	5.01 k allocs: 0.0764 MB	1
basic/@py/pydict/pydel	5.01 k allocs: 0.0764 MB	5.01 k allocs: 0.0764 MB	1
basic/julia/pydict/init	4.01 k allocs: 0.0612 MB	4.01 k allocs: 0.0612 MB	1
basic/julia/pydict/pydel	4.01 k allocs: 0.0612 MB	4.01 k allocs: 0.0612 MB	1
gc/full	0 allocs: 0 B	0 allocs: 0 B
time_to_load	0.143 k allocs: 10.6 kB	0.143 k allocs: 10.6 kB	1