refactor scripts: ensure files end with a newline for consistency and adherence to conventions

Author: allnes

scripts/create_perf_table.py

@@ -102,4 +102,4 @@
             IT_I += 1
         IT_I = 2
 
-    workbook.close()
+    workbook.close()

scripts/jobs_graph.py

@@ -50,4 +50,4 @@ def save_graph(dot, filename, file_format):
     svg_path = os.path.join("docs", "_static", "ci_graph")
     gha_data = parse_gha_yml(gha_file_path)
     jobs_graph = build_jobs_graph(gha_data)
-    save_graph(jobs_graph, svg_path, "svg")
+    save_graph(jobs_graph, svg_path, "svg")

scripts/variants_generation.py

@@ -67,4 +67,4 @@ def generate_group_table(_num_tasks, _num_students, _num_variants, _csv_file):
 
     for num_students, index in zip(list_students, range(len(list_students))):
         csv_path = path_to_results / f'variants_group_{index + 1}.csv'
-        generate_group_table(NUM_TASKS, num_students, num_variants, csv_path.as_posix())
+        generate_group_table(NUM_TASKS, num_students, num_variants, csv_path.as_posix())