Option to disable dependency tracking

[novemberborn]

Dependency tracking may be fraught in CommonJS and currently doesn't work anyway in ESM. See discussion in #2887 and #2388.

When dependency tracking breaks, watch mode becomes less useful. Let's add a trackDependencies configuration option, defaulting to true, which when set to false disables dependency tracking. We can add a guard here:

ava/lib/worker/base.js

Line 159 in 77623a5

dependencyTracking.install(require.extensions, testPath);

Presumably the solution for #2388 will involve parsing syntax files which may be slow, so having an opt out will be useful regardless.

[Sarveshk76]

Is it right?

[novemberborn]

This would be irrelevant if #3123 is completed.