add import linter

Author: Jannis-Mittenzwei

poetry.lock

@@ -56,6 +56,7 @@ shibuya = ">=2024.5.14"
 sphinx-design = ">=0.5.0,<1"
 
 
+import-linter = "^2.0"
 [tool.poetry.group.dev.dependencies]
 autoimport = "^1.4.0"
 
@@ -108,3 +109,11 @@ ignore_errors = true
 
 [tool.poetry.scripts]
 tbx = 'exasol.toolbox.tools.tbx:CLI'
+
+[tool.importlinter]
+root_package = "exasol.toolbox"
+include_external_packages = true
+
+[[tool.importlinter.contracts]]
+name = "contract test"
+type = "independence"