Bump phpunit/phpunit from 7.5.11 to 7.5.12

Bumps [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) from 7.5.11 to 7.5.12.
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/master/ChangeLog-7.5.md)
- [Commits](https://github.com/sebastianbergmann/phpunit/compare/7.5.11...7.5.12)

composer.lock

@@ -1949,16 +1949,16 @@
         },
         {
             "name": "phpunit/phpunit",
-            "version": "7.5.11",
+            "version": "7.5.12",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/phpunit.git",
-                "reference": "64cb33f5b520da490a7b13149d39b43cf3c890c6"
+                "reference": "9ba59817745b0fe0c1a5a3032dfd4a6d2994ad1c"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/phpunit/zipball/64cb33f5b520da490a7b13149d39b43cf3c890c6",
-                "reference": "64cb33f5b520da490a7b13149d39b43cf3c890c6",
+                "url": "https://api.github.com/repos/sebastianbergmann/phpunit/zipball/9ba59817745b0fe0c1a5a3032dfd4a6d2994ad1c",
+                "reference": "9ba59817745b0fe0c1a5a3032dfd4a6d2994ad1c",
                 "shasum": ""
             },
             "require": {
@@ -2029,7 +2029,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2019-05-14T04:53:02+00:00"
+            "time": "2019-05-28T11:59:40+00:00"
         },
         {
             "name": "psr/log",