change collections rewrite slug

src/classes/repositories/class-tainacan-collections.php

@@ -245,7 +245,8 @@ class Collections extends Repository {
 			'has_archive'         => true,
 			'query_var'           => true,
 			'can_export'          => true,
-			'rewrite'             => true,
+			/* Translators: The Collections slug - will be the URL for the collections archive */
+			'rewrite'             => ['slug' => sanitize_title(_x('collections', 'Slug: the string that will be used to build the URL', 'tainacan'))],
 			'capability_type'     => Entities\Collection::get_capability_type(),
 			'map_meta_cap'        => true,
 			'supports'            => [

src/migrations.php

@@ -274,6 +274,11 @@ class Migrations {
         }
 	}
 
+	static function refresh_rewrite_rules() {
+		// needed after we changed the Collections post type rewrite slug
+		flush_rewrite_rules(false);
+	}
+	
 }