[analysis-scripts] apply several pyflakes, pylint, black suggestions

share/analysis-scripts/benchmark_database.py

share/analysis-scripts/build.py

share/analysis-scripts/build_callgraph.py

share/analysis-scripts/detect_recursion.py

share/analysis-scripts/estimate_difficulty.py

share/analysis-scripts/find_fun.py

share/analysis-scripts/frama_c_results.py

share/analysis-scripts/function_finder.py

share/analysis-scripts/git_utils.py

share/analysis-scripts/heuristic_list_functions.py

share/analysis-scripts/list_files.py

share/analysis-scripts/make_wrapper.py

share/analysis-scripts/normalize_jcdb.py

share/analysis-scripts/print_callgraph.py

share/analysis-scripts/results_display.py

share/analysis-scripts/source_filter.py

share/analysis-scripts/summary.py