Install composer viea phive and remove phpunit from composer dev install

Update comoser test files to work with both, but primary is the phive
installed one.

run tests via 4dev/check/phpunit.sh as before

4dev/tests/Get/CoreLibsGetSystemTest.php

@@ -99,7 +99,7 @@ final class CoreLibsGetSystemTest extends TestCase
 				1 => 'phpunit',
 				2 => 'phpunit',
 				// NOTE: this can change, so it is a regex check
-				3 => "/^(\/?.*\/?)?vendor\/bin\/phpunit$/",
+				3 => "/^(\/?.*\/?)?(vendor\/bin|tools)\/phpunit$/",
 			],
 			'some path with extension' => [
 				0 => '/some/path/to/file.txt',