[!163][SUBTITLING] Fix help print in subtitle compliance script

# Why is the change needed?

The help command for the subtitle compliance script does not work.

# What changes does the patch introduce?

Escapes the characters so that the help properly works.

# How was this patch tested?

manual run

Author: mgaido91

examples/speech_to_text/scripts/subtitle_compliance.py

@@ -290,7 +290,7 @@ def main(args):
         help='floating point width.')
     parser.add_argument(
         '--confidence-intervals', '-ci',  default=False, action='store_true',
-        help='confidence intervals with 95% confidence level using bootstrap resampling '
+        help='confidence intervals with 95%% confidence level using bootstrap resampling '
              f'({_BOOTSTRAP_NUM_SAMPLES} samples). The number of samples can be customized by '
              'setting the environment variable BOOTSTRAP_NUM_SAMPLES.')
     parser.add_argument(