build(deps-dev): bump phpunit/phpunit in /build/integration

Bumps [phpunit/phpunit](https://github.com/sebastianbergmann/phpunit) from 9.6.18 to 9.6.19.
- [Release notes](https://github.com/sebastianbergmann/phpunit/releases)
- [Changelog](https://github.com/sebastianbergmann/phpunit/blob/9.6.19/ChangeLog-9.6.md)
- [Commits](https://github.com/sebastianbergmann/phpunit/compare/9.6.18...9.6.19)

---
updated-dependencies:
- dependency-name: phpunit/phpunit
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

build/integration/composer.lock

@@ -1201,16 +1201,16 @@
         },
         {
             "name": "phpunit/phpunit",
-            "version": "9.6.18",
+            "version": "9.6.19",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/phpunit.git",
-                "reference": "32c2c2d6580b1d8ab3c10b1e9e4dc263cc69bb04"
+                "reference": "a1a54a473501ef4cdeaae4e06891674114d79db8"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/phpunit/zipball/32c2c2d6580b1d8ab3c10b1e9e4dc263cc69bb04",
-                "reference": "32c2c2d6580b1d8ab3c10b1e9e4dc263cc69bb04",
+                "url": "https://api.github.com/repos/sebastianbergmann/phpunit/zipball/a1a54a473501ef4cdeaae4e06891674114d79db8",
+                "reference": "a1a54a473501ef4cdeaae4e06891674114d79db8",
                 "shasum": ""
             },
             "require": {
@@ -1284,7 +1284,7 @@
             "support": {
                 "issues": "https://github.com/sebastianbergmann/phpunit/issues",
                 "security": "https://github.com/sebastianbergmann/phpunit/security/policy",
-                "source": "https://github.com/sebastianbergmann/phpunit/tree/9.6.18"
+                "source": "https://github.com/sebastianbergmann/phpunit/tree/9.6.19"
             },
             "funding": [
                 {
@@ -1300,7 +1300,7 @@
                     "type": "tidelift"
                 }
             ],
-            "time": "2024-03-21T12:07:32+00:00"
+            "time": "2024-04-05T04:35:58+00:00"
         },
         {
             "name": "psr/container",