Add ARM C++ target architecture testing to CI build

[kaby76]

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As per #2567, we need to add more testing, this time for ARM C++ targets.

Adding ARM testing will probably add to the list of "symbol conflicts" for the Cpp target, e.g., NAN VOERFLOW, and update the grammars.

Also, we only test Antlr 4.9.3 at the moment, and likely very soon Antlr 4.10. We don't test older versions of Antlr, but we should.