ConfigFileNotFound exception + run-test script

Signed-off-by: Václav Valíček <valicek1994@gmail.com>

repo_cloner/lib/config_file_not_found_error.py

@@ -0,0 +1,20 @@
+from pathlib import PosixPath
+import os
+
+
+class ConfigFileNotFoundError(OSError):
+
+	def __str__(self):
+		if len(self.args) == 2:
+			path: str = ""
+			filename: str = ""
+			if isinstance(self.args[0], PosixPath):
+				path = str(PosixPath(self.args[0]))
+			else:
+				path = str(self.args[0])
+
+			filename = str(self.args[1])
+			path = os.path.join(path, filename)
+			return f"Config file does not exist: {path}"
+		else:
+			return super.__str__(self)