feat: add benchmarks to CI

[rjwalters]

Goal is to use:

• pytest-benchmark
• bencher github action
• RunsOn (so that we can run tests on gpu machines on amazon)

I am also updating and repairing the test suite as I go

[github-actions]

Bencher Report

Branch	robb/0421-add-bencher-action
Testbed	ubuntu-latest

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• Step (nanoseconds (ns))

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Click to view all benchmark results

Benchmark	Step	microseconds (µs)
tests/test_bench_map_mapgen.py::test_scene_gen[/scenes/convchain/blob]	📈 view plot ⚠️ NO THRESHOLD	293,195.19 µs
tests/test_bench_map_mapgen.py::test_scene_gen[/scenes/convchain/c_shape]	📈 view plot ⚠️ NO THRESHOLD	760,353.26 µs
tests/test_bench_map_mapgen.py::test_scene_gen[/scenes/convchain/diagonal]	📈 view plot ⚠️ NO THRESHOLD	744,577.82 µs
tests/test_bench_map_mapgen.py::test_scene_gen[/scenes/wfc/blob]	📈 view plot ⚠️ NO THRESHOLD	505,672.27 µs
tests/test_bench_map_mapgen.py::test_scene_gen[/scenes/wfc/simple]	📈 view plot ⚠️ NO THRESHOLD	140,138.79 µs
tests/test_bench_mettagrid_env.py::test_combined_performance	📈 view plot ⚠️ NO THRESHOLD	125.86 µs
tests/test_bench_mettagrid_env.py::test_get_stats_performance	📈 view plot ⚠️ NO THRESHOLD	1.98 µs
tests/test_bench_mettagrid_env.py::test_step_performance	📈 view plot ⚠️ NO THRESHOLD	116.50 µs

🐰 View full continuous benchmarking report in Bencher

[rjwalters]

moved to https://github.com/Metta-AI/metta/pull/216