Remove pytest constraint

Author: ladinesa

pyproject.toml

@@ -21,11 +21,11 @@ homepage = "https://github.com/nomad-coe/database-parsers"
 
 [project.optional-dependencies]
 tests = [
-    "pytest>= 5.3.0, <= 8.0.2",
-    "pytest-cov==2.7.1",
+    "pytest",
+    "pytest-cov",
     "astroid>=2.5.1",
     'mypy>=1.15',
-    'ruff>=0.6',
+    'ruff',
     'typing-extensions>=4.12',
 ]