Adds a "Request password" button to the public share authentication page for shares

Adds a "Request password" button to the public share authentication page for shares
of type TYPE_EMAIL, when the "video verification" checkbox isn't checked. Users accessing
non-anonymous public shares (TYPE_EMAIL shares) can now request a temporary password themselves.

- Creates a migration step for the files_sharing app to add the 'password_expiration_time'
  attribute to the oc_shares table.
- Makes share temporary passwords' expiration time configurable via a system value.
- Adds a system config value to allow permanent share passwords

-Fixes a typo in a comment in apps/files_sharing/src/components/SharingEntryLink.vue

See https://github.com/nextcloud/server/issues/31005

Signed-off-by: Cyrille Bollu <cyrpub@bollu.be>