Print VerificationError message instead of variant

[rlukata]

This PR changes how Debug behaves on the VerificationError struct. Instead of printing the variant of the struct, it uses the Display format to print the custom message.

[github-actions]

Benchmark for Linux-cuda 981c691

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Test	Base	PR	%
fib/100/execute	5.3±0.09ms	5.2±0.10ms	-1.89%
fib/100/prove	1530.8±41.06ms	775.1±4.02ms	-49.37%
fib/100/total	1451.7±10.75ms	783.2±3.57ms	-46.05%
fib/1000/execute	5.8±0.15ms	5.7±0.10ms	-1.72%
fib/1000/prove	1514.3±30.43ms	805.1±1.85ms	-46.83%
fib/1000/total	1493.5±24.15ms	814.6±5.26ms	-45.46%
fib/10000/execute	10.6±0.20ms	10.6±0.34ms	0.00%
fib/10000/prove	4.7±0.01s	3.2±0.01s	-31.91%
fib/10000/total	4.7±0.02s	3.2±0.01s	-31.91%

Benchmark for Linux-default

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Benchmark for macOS-default

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Benchmark for macOS-metal 981c691

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Test	Base	PR	%
fib/100/execute	2.8±0.05ms	2.7±0.14ms	-3.57%
fib/100/prove	851.1±5.92ms	849.9±4.80ms	-0.14%
fib/100/total	879.4±6.47ms	872.1±6.09ms	-0.83%
fib/1000/execute	3.0±0.06ms	2.9±0.10ms	-3.33%
fib/1000/prove	870.9±3.05ms	870.7±3.06ms	-0.02%
fib/1000/total	902.3±5.95ms	890.6±5.11ms	-1.30%
fib/10000/execute	5.1±0.07ms	5.0±0.07ms	-1.96%
fib/10000/prove	3.3±0.01s	3.3±0.02s	0.00%
fib/10000/total	3.3±0.01s	3.3±0.01s	0.00%