build: partially revert recent arm64 changes

[reubeno]

We've been running into internal compiler errors compiling for arm64 since #335 . For now, we'll revert most of that change to unblock other work.

[github-actions]

Test Results

    2 files      9 suites   1m 42s ⏱️
  621 tests   621 ✅ 0 💤 0 ❌
1 228 runs  1 228 ✅ 0 💤 0 ❌

Results for commit d0866ca.

[github-actions]

Performance Benchmark Report

Benchmark name	Baseline (μs)	Test/PR (μs)	Delta (μs)	Delta %
clone_shell_object	16.28 μs	16.36 μs	0.08 μs	🟠 +0.50%
eval_arithmetic	0.20 μs	0.18 μs	-0.01 μs	🟢 -6.67%
expand_one_string	1.55 μs	1.53 μs	-0.02 μs	⚪ Unchanged
for_loop	32.33 μs	32.64 μs	0.31 μs	⚪ Unchanged
function_call	3.61 μs	3.32 μs	-0.29 μs	⚪ Unchanged
instantiate_shell	48.28 μs	48.49 μs	0.21 μs	⚪ Unchanged
instantiate_shell_with_init_scripts	22269.44 μs	22539.19 μs	269.75 μs	⚪ Unchanged
parse_bash_completion	1665.14 μs	1650.49 μs	-14.65 μs	⚪ Unchanged
parse_sample_script	1.75 μs	1.75 μs	-0.00 μs	⚪ Unchanged
run_echo_builtin_command	15.96 μs	16.05 μs	0.09 μs	⚪ Unchanged
run_one_external_command	2464.95 μs	2094.75 μs	-370.20 μs	🟢 -15.02%
tokenize_sample_script	2.76 μs	2.76 μs	0.00 μs	⚪ Unchanged

Code Coverage Report: Only Changed Files listed

Package	Base Coverage	New Coverage	Difference
brush-core/src/builtins/dot.rs	🟢 91.67%	🟢 95.83%	🟢 4.16%
brush-core/src/builtins/return_.rs	🟢 81.82%	🟢 100%	🟢 18.18%
brush-core/src/jobs.rs	🔴 43.1%	🔴 37.07%	🔴 -6.03%
brush-core/src/shell.rs	🟢 77.62%	🟢 78.34%	🟢 0.72%
Overall Coverage	🟢 74.7%	🟢 74.68%	🔴 -0.02%

Minimum allowed coverage is 70%, this run produced 74.68%