feat(web) add hover background to image toolbar icons (#4402)

* feat: add hover background to image toolbar icons

* not use background color when not set

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Co-authored-by: katsadim <athanasios.katsadimas@refurbed.com>
Co-authored-by: Alex Tran <alex.tran1502@gmail.com>

web/src/lib/components/elements/buttons/circle-icon-button.svelte

@@ -2,7 +2,7 @@
   import type Icon from 'svelte-material-icons/AbTesting.svelte';
 
   export let logo: typeof Icon;
-  export let backgroundColor = 'transparent';
+  export let backgroundColor = '';
   export let hoverColor = '#e2e7e9';
   export let padding = '3';
   export let size = '24';