Interference between `autosave` and `eofnewline`

By enabling both the features, one could ensure, that their work won't be accidentally lost and it also looks pretty. However, enabling both of them would insert newlines randomly while typing some text, as the automatic save is triggered every 8 seconds, and if one happens to type on the end of the file, the cursor jumps to the new line automatically, and text will be magically broken into two separate line.

Reproduce the issue in micro with both autosave and eofnewline enabled, typing at the end of a file while the 8-second save occurs. Trace the autosave and eofnewline handling to find where the newline changes the cursor or file during typing. Done means automatic saves no longer insert a newline or split text when both features are enabled.