todoist: keyring implementation for storing todoist token

The patch introduces method to store todoist access_token
into keyring and identifies the user details using the
token.
1 job for keyring in 8 minutes and 17 seconds (queued for 26 minutes and 52 seconds)
latest
Status Job ID Name Coverage
  Flatpak
passed #75402
flatpak:master

00:08:17