Set minHeight of the password field in Shared Hotspot

- Set minHeight to @dimen/min_tap_target_size(48dp)

Fix: 318617636
Test: unit test
make RunSettingsRoboTests ROBOTEST_FILTER=com.android.settings.wifi.dpp

Change-Id: I794862bac82eb37b168263e2e472cba26ba34647

res/layout/wifi_dpp_qrcode_generator_fragment.xml

@@ -55,6 +55,7 @@
                 android:id="@+id/password"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
+                android:minHeight="@dimen/min_tap_target_size"
                 android:layout_marginBottom="24dp"
                 android:textAlignment="center"
                 android:textIsSelectable="true"