TestSampler/Abort is flaky

[lthibault]

=== CONT  TestSampler/Abort
    sampler_test.go:110: stopped
    sampler_test.go:75: 
        	Error Trace:	/home/runner/work/casm/casm/pkg/debug/sampler_test.go:75
        	Error:      	Not equal: 
        	            	expected: 50ms
        	            	actual  : 100ms
        	Test:       	TestSampler/Abort
        	Messages:   	should run for 50ms

I don't think there's an actual problem here. It's likely that the test is too sensitive.