chore(auth): adds update password and fetch session to auth example

[haverchuck]

Description of changes: Adds update password and fetch session to auth example app.

Note: I wasn't quite sure how to change the black background on the expansion panel list. Not worrying about it too much right now.

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[codecov-commenter]

Codecov Report

Merging #1699 (200521f) into next (f91746c) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##             next    #1699   +/-   ##
=======================================
  Coverage   44.49%   44.49%           
=======================================
  Files         121      121           
  Lines        7493     7493           
=======================================
  Hits         3334     3334           
  Misses       4159     4159           

Flag	Coverage Δ
android-unit-tests	∅ <ø> (∅)
flutter-unit-tests	27.25% <ø> (ø)
ios-unit-tests	89.08% <ø> (ø)

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