Lists "travel" when switching from unordered to ordered lists

**Describe the bug**
Editor adds an empty whitespace each time you switch from unordered to ordered lists.

**To Reproduce**
Steps to reproduce the behavior:
1. Select multiple lines of text
2. Switch between unordered and ordered lists over and over again
3. Observe that there is an additional whitespace get added
4. Observe the "travel" when repeatedly doing this

**Expected behavior**
Switching between unordered and ordered lists should be seamless and result in no added characters.

**Screenshots**


**Version information**
- OS: macOS
- Browser: Safari, Latest Version
- EasyMDE version: Default, latest

**Additional context**
Great work on the editor!