Add option to pass FOCUS spec version to validate against

Useful when you compose conversion rules for a vertion different than
default (0.5 at the moment in pip package of focus-validator)

Signed-off-by: Stanislav Hanzhin-Tsvetkov <hanzhin.stas@gmail.com>

focus_converter_base/focus_converter/main.py

@@ -52,6 +52,13 @@ def main(
             rich_help_panel="Validation",
         ),
     ] = False,
+    spec_version: Annotated[
+            str,
+            typer.Option(
+                help="Validate generated data to match particular FOCUS spec. version",
+                rich_help_panel="Validation",
+            ),
+        ] = "0.5",
 ):
     # compute function for conversion
 
@@ -81,6 +88,7 @@ def main(
                 data_filename=file_path,
                 output_type="console",
                 output_destination=None,
+                rules_version=spec_version,
             )
             validator.load()
             validator.validate()