Update dependency league/commonmark to ^2.8.1 [SECURITY]

| datasource | package           | from  | to    |
| ---------- | ----------------- | ----- | ----- |
| packagist  | league/commonmark | 2.7.1 | 2.8.1 |


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

Author: renovate[bot]

composer.json

@@ -47,7 +47,7 @@
         "laminas/laminas-paginator": "^2.19.0",
         "laminas/laminas-servicemanager": "^3.23.1",
         "laminas/laminas-stdlib": "^3.20.0",
-        "league/commonmark": "^2.7.1",
+        "league/commonmark": "^2.8.1",
         "mezzio/mezzio": "^3.22.1",
         "mezzio/mezzio-fastroute": "^3.13.0",
         "mezzio/mezzio-helpers": "^5.19.0",