chore: remove useless persistent install instructions

eDrive is an application provided by default with /e/OS.

It synchronizes user's data files to /e/Cloud or a self-hosted cloud.

## Install

Since the application is persistent, you won't be able to reinstall

the app with a regular `adb install -r` command. You will have to

allow root debugging in the Developer Options, then

`adb root && adb remount`, then `adb push eDrive.apk /system/app/eDrive/eDrive.apk`

and finally `adb reboot`.

## Map of synced directories

| device                               | cloud                                  | category     |