Refactor conditional function definitions

Function definitions within a condition do not function as expected thanks to JS hoisting, so it is better to avoid it, and keep ESLint happy as well.

See discussion at #8622 with @pmario

plugins/tiddlywiki/multiwikiserver/modules/store/tests-sql-tiddler-database.js

@@ -6,14 +6,13 @@ tags: [[$:/tags/test-spec]]
 Tests the SQL tiddler database layer
 
 \*/
+if($tw.node) {
 (function(){
 
 /*jslint node: true, browser: true */
 /*global $tw: false */
 "use strict";
 
-if($tw.node) {
-
 describe("SQL tiddler database with node-sqlite3-wasm", function() {
 	runSqlDatabaseTests("wasm");
 });
@@ -107,6 +106,6 @@ function runSqlDatabaseTests(engine) {
 	});
 }
 
-}
-
 })();
+
+}