message: Fix docstring format of tf.executing_eagerly
diff: @@ -1877,9 +1877,8 @@ def executing_eagerly():
  True
  False
  - Inside `tf.function` after
  + Inside `tf.function` after `tf.config.run_functions_eagerly(True)` is called:
  - `tf.config.run_functions_eagerly(True)` is called:
  >>> tf.config.run_functions_eagerly(True)
  >>> @tf.function
  ... def fn():
  