[Verify Session] Design fixes (#230)

* Design fixes.

* Make text in emoji items secondary color and the snackbar duration short again

* Try to make margins smaller on smaller displays

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Co-authored-by: Florian Renaud <florianr@element.io>

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/ElementTextStyles.kt

@@ -26,7 +26,7 @@ import androidx.compose.ui.unit.sp
 object ElementTextStyles {
 
     val Button = TextStyle(
-        fontSize = 17.sp,
+        fontSize = 16.sp,
         fontWeight = FontWeight.Bold,
         lineHeight = 22.sp,
         fontStyle = FontStyle.Normal,