py-openpyxl: updated to 2.5.3

2.5.3:
Bugfixes:
* Warning level too aggressive.
* Alignment and protection values not saved for named styles.
* Deleting elements from a legend doesn窶冲 work.
* Index names repeated for every row in dataframe.
* Worksheet protection not being stored.
* Exception raised when reading a tooltip.

(adam)