[JENKINS-47393] Remove signature and runtime references to CommandLauncher

[jglick]

For jenkinsci/jenkins#3076.

@reviewbybees

[ghost]

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[oleg-nenashev]

Would it be possible to do the change in a compatible way, e.g. by introducing bridge methods and requiring the detached plugin to be installed?

The change introduces a breaking change in the JTH library, and IMHO it needs to be justified at least

[jglick]

introducing bridge methods

Oh no.

introduces a breaking change in the JTH library

Unlikely to be source-incompatible (not that we care greatly), and binary incompatibility is irrelevant.

[oleg-nenashev]

Binary compatibility may be important for things like PCT, which probably bump JTH. But I agree it's not a blocker for the test framework (though it may cause fun for plugins shipping tests artifacts).

The code itself LGTM, hence 🐝

[jglick]

things like PCT, which probably bump JTH

AFAIK it does not. That was in fact one of the benefits of splitting jenkins-test-harness into its own repository and giving it an independent lifecycle: that a plugin POM could declare a specific jenkins-test-harness.version which would remain consistent even when running with a newer jenkins.version during something like PCT (or jenkinsVersions of buildPlugin, etc.).