Use BiometricPrompt description field for CC description instead

The description field handles longer strings more gracefully

Fixes: 124001277

Test: 1) Open Wi-Fi picker
      2) Select gear on the connected network
      3) Select share button
      4) On BiometricPrompt, text is not cropped

Change-Id: I945830a137a0dc203bba04728b507ceff020dfdc