Fix T74959: Need to be explicit about UTF8 encoding in py.

Because some OSs are still using old 8bits specific encodings... Angry
eye @windows...

release/scripts/modules/bl_i18n_utils/utils.py

@@ -1158,7 +1158,7 @@ class I18n:
             print("WARNING: skipping file {}, too huge!".format(path))
             return None, None, None, False
         txt = ""
-        with open(path) as f:
+        with open(path, encoding="utf8") as f:
             txt = f.read()
         _in = 0
         _out = len(txt)
@@ -1544,7 +1544,7 @@ class I18n:
                 "",
                 self.settings.PARSER_PY_MARKER_END,
             ]
-        with open(dst, 'w') as f:
+        with open(dst, 'w', encoding="utf8") as f:
             f.write((prev or "") + "\n".join(txt) + (nxt or ""))
         self.unescape()