use @nextcloud/vue-richtext 2.1.0-beta.6 which fixes the circular dependency

Signed-off-by: Julien Veyssier <julien-nc@posteo.net>

Author: julien-nc

package-lock.json

@@ -52,7 +52,7 @@
 		"@nextcloud/l10n": "^2.0.1",
 		"@nextcloud/logger": "^2.2.1",
 		"@nextcloud/router": "^2.0.0",
-		"@nextcloud/vue-richtext": "^2.1.0-beta.5",
+		"@nextcloud/vue-richtext": "^2.1.0-beta.6",
 		"@nextcloud/vue-select": "^3.21.2",
 		"@skjnldsv/sanitize-svg": "^1.0.2",
 		"debounce": "1.2.1",