Uninstall

Remove Capslock, its data, and its permission entry, and make sure Caps Lock is back to normal.

Capslock has no installer and leaves nothing outside your user account except the Accessibility entry.

Quit Capslock from the menu-bar icon or with ⌘Q, so it can give Caps Lock back. If it was force-quit and Caps Lock still does not work as usual, run the restore command before you delete the app.
If you turned on Open at login, turn it off in Settings › General.
Move /Applications/Capslock.app to the Trash.
To remove your data as well, delete these:
- ~/Library/Application Support/com.vonng.capslock
- ~/Library/Preferences/com.vonng.capslock.plist
- ~/Library/Caches/com.vonng.capslock
In System Settings › Privacy & Security › Accessibility, select Capslock and click −.
If you used clipboard slots, delete the Keychain item named com.vonng.capslock.clipboard-slots in Keychain Access.

A Mac restart also clears the Caps Lock mapping, which macOS does not keep across restarts.