fix: snakemake warnings (#1785)

Author: lkstrp

Snakefile

@@ -131,21 +131,17 @@ rule all:
             run=config["run"]["name"],
             carrier=config_provider("plotting", "balance_map", "bus_carriers")(w),
         ),
-        directory(
-            expand(
-                RESULTS
-                + "graphics/balance_timeseries/s_{clusters}_{opts}_{sector_opts}_{planning_horizons}",
-                run=config["run"]["name"],
-                **config["scenario"],
-            ),
+        expand(
+            RESULTS
+            + "graphics/balance_timeseries/s_{clusters}_{opts}_{sector_opts}_{planning_horizons}",
+            run=config["run"]["name"],
+            **config["scenario"],
         ),
-        directory(
-            expand(
-                RESULTS
-                + "graphics/heatmap_timeseries/s_{clusters}_{opts}_{sector_opts}_{planning_horizons}",
-                run=config["run"]["name"],
-                **config["scenario"],
-            ),
+        expand(
+            RESULTS
+            + "graphics/heatmap_timeseries/s_{clusters}_{opts}_{sector_opts}_{planning_horizons}",
+            run=config["run"]["name"],
+            **config["scenario"],
         ),
     default_target: True