BUG: read_excel for ods files raising UnboundLocalError in certain cases
- [x] closes #36122 
- [x] closes #35802
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

Need some guidance on tests here. Do we need tests for other file formats here as well? Also unsure about naming conventions.

The primary bug in this case (apart from the indentation problem in the original code) is that the code was ignoring cases where the XML of the cell had multiple child nodes that were not spaces

reverted implementation from #33233 incorporating part of its modifications.
Looks good - can you add a what’s new note for 1.2 bug fix section? @WillAyd added what's new note thanks @asishm  from https://github.com/pandas-dev/pandas/issues/36122#issue-693379165

> This used to work fine (one month ago on my machine). I tried upgrading to Pandas 1.1.1 and get the same bug. It looks like what's below:

could this fix go in 1.1.3 yep could backport ok will raise PR on master first to move release note and then do a manual backport.

can't auto backport this (followed by release note move) as no doc/source/whatsnew/v1.2.0.rst on 1.1.x > ok will raise PR on master first to move release note and then do a manual backport.

second thoughts will do the backport first and then if all ok move release note on master to be in sync