fix(NcIconSvgWrapper): Fix icon size variable being undefined

Use CSS variable with `style` binding instead, as the `v-bind` generated an undefined CSS variable.
(Yet for the next branch, Vue 3, it seems to work).

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

src/components/NcIconSvgWrapper/NcIconSvgWrapper.vue

@@ -180,6 +180,7 @@ export default {
 		 * Icon size used in CSS
 		 */
 		iconSize() {
+			console.warn('foo', typeof this.size === 'number' ? `${this.size}px` : this.size, 'FF')
 			return typeof this.size === 'number' ? `${this.size}px` : this.size
 		},
 
@@ -206,6 +207,9 @@ export default {
 		attributes() {
 			return {
 				class: ['icon-vue', { 'icon-vue--inline': this.inline }],
+				style: {
+					' --icon-size': this.iconSize,
+				},
 				role: 'img',
 				'aria-hidden': !this.name ? true : undefined,
 				'aria-label': this.name || undefined,
@@ -233,10 +237,10 @@ export default {
 
 	&:deep(svg) {
 		fill: currentColor;
-		width: v-bind('iconSize');
-		height: v-bind('iconSize');
-		max-width: v-bind('iconSize');
-		max-height: v-bind('iconSize');
+		width: var(--icon-size, 20px);
+		height: var(--icon-size, 20px);
+		max-width: var(--icon-size, 20px);
+		max-height: var(--icon-size, 20px);
 	}
 }
 </style>