Add timeout to process codebase and plugin steps

[AyanSinhaMahapatra]

Reference:

• fast-scan: Create scan benchmark for package detection in ScanCode Toolkit #4061

Tasks

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• Updated CHANGELOG.rst (if applicable)

[AyanSinhaMahapatra]

Need some review there wrt. the default behaviour there, as these timeouts can cause weird issues/crashes elsewhere, so should we just keep this only as a CLI option which can be enabled to set a timeout, or have a default timeout like we have in the file-level scan timeout. If we have this as a default we also have to decide on a reasonable timeout duration.