The `.` (last inserted text) register gets updated with `<C-a>` instead of the actual inserted text, after using `<C-a>` in Insert mode

[RigoTamas]

Describe the bug

After using the <C-A> key in insert mode and then leaving insert mode, the . register gets updated with <C-A> instead of the actual text that was inserted. If I then enter insert mode again, and use <C-A> again, nothing is inserted, as the <C-A> would use the . register to insert text. Therefore, <C-A> can be used only once, which is unfortunate.

To Reproduce

1. Enter insert mode, write some text.
2. Leave insert mode.
3. Enter insert mode again, press <C-A>, and see that your last written text is inserted.
4. Leave insert mode.
5. Enter insert mode again, press <C-A>, and see that nothing is inserted

Expected behavior

The second time I enter insert mode and use <C-A>, I would expect that it again inserts the text that was last inserted. This would be possible, if the . register would be updated with the actual text, and not with <C-A>

Environment:

• Extension (VsCodeVim) version: 1.18.9
• VSCode version: 1.53.1
• OS: macOS Catalina, version: 10.15.7