scripts: new linter script to detect goal_src files with trailing whitespace (#3387)

Removes trailing whitespace from goal_src files, eventually the
formatter will do this as well but it's not ready yet so this is a
decent interim solution.

A competent text editor will also do this / flag it for you.

scripts/ci/lint-trailing-whitespace.py

@@ -0,0 +1,40 @@
+import glob
+import re
+
+import argparse
+
+parser = argparse.ArgumentParser()
+parser.add_argument("--fix", action="store_true")
+parser.set_defaults(fix=False)
+args = parser.parse_args()
+
+folders_to_check = ["goal_src"]
+
+flagged_instances = []
+
+for folder in folders_to_check:
+  files_to_check = glob.glob("./{}/**/*.gc".format(folder), recursive=True)
+  files_to_check += glob.glob("./{}/**/*.gs".format(folder), recursive=True)
+  files_to_check += glob.glob("./{}/**/*.gd".format(folder), recursive=True)
+  for filename in files_to_check:
+    # Get the file contents
+    with open(filename, "r", encoding="utf-8") as f:
+      lines = f.readlines()
+      lines_with_trailing_whitespace = [line.rstrip('\n').endswith(' ') for line in lines]
+      if any(lines_with_trailing_whitespace):
+        flagged_instances.append(filename)
+        if args.fix:
+          cleaned_lines = [line.rstrip() + '\n' if line.rstrip() != line else line for line in lines]
+          with open(filename, 'w') as file:
+            file.writelines(cleaned_lines)
+
+if len(flagged_instances) == 0:
+  exit(0)
+
+if args.fix:
+  print("Fixed whitespace in {} files:".format(len(flagged_instances)))
+else:
+  print("Found empty whitespace in the following files, please trim them:")
+  for file in flagged_instances:
+    print(file)
+  exit(1)