RFR: JDK-8326389: [test] improve assertEquals failure output [v3]

[Christoph Langer]

On Sat, 24 Feb 2024 11:45:46 GMT, Jaikiran Pai <jpai at openjdk.org> wrote:

> This is similar to what other test libraries usually report for such failures.

But in the case of a non-empty `msg` you would not see the actual values any more which I think could be helpful in a lot of cases...

-------------

PR Comment: https://git.openjdk.org/jdk/pull/17952#issuecomment-1962412001