Fix an issue where data-elses were being resolved twice, which was incorrect. Fixes #45253.
Merge pull request #45258 from jeresig/fix-45253

Fix an issue where data-elses were being resolved twice, which was incorrect. Fixes #45253.
Add in some tests for data-if/data-else handling. Change the script to not modify node with a class of 'problem' or 'question'.
Don't use entities inside data-if expressions, makes it easier to read.
Fix linting issue.
Run clean-exercises on the HTML exercises, fixing the entities inside the data-if attributes.
Back out latest lint fix.
Merging in with master.
Re-run the linter on the exercises, fixing data-if usage and replacing entities with characters in data-if attributes.