[5.8] Replace deprecated phpunit <7.5.0 methods

[imanghafoori1]

replace deprecated phpunit methods with new ones

see this link :

sebastianbergmann/phpunit#3368

Note that the composer.json file now requires phpunit 7.5 or more

[imanghafoori1]

This tests fail in the env:lowest config.
because in that case phpunit version is 7.0.0

[devcircus]

Is there anything stopping us from bumping the minimum requirement for phpunit in 5.8 to 7.5?

[imanghafoori1]

I do not know
I reopen the issue so that the members can decide on that.
It should be bumped up from ^7.0 to ^7.5
It does not seem to be problematic.

[GrahamCampbell]

Please send this to the 5.7 branch, since all these changes only affect the tests, so we can safely bumb the minimum version of phpunit, without it being a breaking change, since it is with respect to testing the framework itself.