Removes deprecated Actionlint problem matcher

Deletes the obsolete Actionlint problem matcher configuration to clean up workflow files and reduce maintenance overhead.

Relates to MLO-469

.github/actionlint-matcher.json

@@ -1,17 +0,0 @@
-{
-    "problemMatcher": [
-        {
-            "owner": "actionlint",
-            "pattern": [
-                {
-                    "code": 5,
-                    "column": 3,
-                    "file": 1,
-                    "line": 2,
-                    "message": 4,
-                    "regexp": "^(?:\\x1b\\[\\d+m)?(.+?)(?:\\x1b\\[\\d+m)*:(?:\\x1b\\[\\d+m)*(\\d+)(?:\\x1b\\[\\d+m)*:(?:\\x1b\\[\\d+m)*(\\d+)(?:\\x1b\\[\\d+m)*: (?:\\x1b\\[\\d+m)*(.+?)(?:\\x1b\\[\\d+m)* \\[(.+?)\\]$"
-                }
-            ]
-        }
-    ]
-}