Add AlmaLinux/CentOS 9 support (#444)

Author: bastelfreak

Diff for: metadata.json

@@ -55,7 +55,8 @@
     {
       "operatingsystem": "AlmaLinux",
       "operatingsystemrelease": [
-        "8"
+        "8",
+        "9"
       ]
     },
     {
@@ -66,6 +67,12 @@
         "9"
       ]
     },
+    {
+      "operatingsystem": "CentOS",
+      "operatingsystemrelease": [
+        "9"
+      ]
+    },
     {
       "operatingsystem": "Ubuntu",
       "operatingsystemrelease": [