fix: Print a clearer message when meltano.yml is empty (meltano#7636)

* print exception message for empty meltano files

* [pre-commit.ci] auto fixes from pre-commit.ci hooks

for more information, see https://pre-commit.ci

* update docstring

* Update src/meltano/core/error.py

Co-authored-by: Edgar R. M. <edgarrm358@gmail.com>

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Edgar R. M. <edgarrm358@gmail.com>

src/meltano/core/error.py

@@ -100,9 +100,15 @@ class PluginInstallWarning(Exception):
     """Exception for when a plugin optional optional step fails to install."""
 
 
-class EmptyMeltanoFileException(Exception):
+class EmptyMeltanoFileException(MeltanoError):
     """Exception for empty meltano.yml file."""
 
+    def __init__(self) -> None:
+        """Instantiate the error."""
+        reason = "Your meltano.yml file is empty"
+        instruction = "Please update your meltano file with a valid configuration"
+        super().__init__(reason, instruction)
+
 
 class MeltanoConfigurationError(MeltanoError):
     """Exception for when Meltano is inproperly configured."""