Update dependency psalm/plugin-phpunit to ^0.20.0

| datasource | package              | from   | to     |
| ---------- | -------------------- | ------ | ------ |
| packagist  | psalm/plugin-phpunit | 0.19.7 | 0.20.2 |


Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

composer.json

@@ -20,7 +20,7 @@
     "laminas/laminas-coding-standard": "~3.1.0",
     "lcobucci/clock": "^3.3.1",
     "lctrs/psalm-psr-container-plugin": "^1.11",
-    "psalm/plugin-phpunit": "^0.19.5",
+    "psalm/plugin-phpunit": "^0.20.0",
     "vimeo/psalm": "^6.15.1"
   },
   "config": {