add semi before reactive-block-wrapping function (#290)

Author: jasonlyu123

packages/svelte2tsx/src/svelte2tsx.ts

@@ -763,7 +763,7 @@ function processInstanceScriptContent(str: MagicString, script: Node): InstanceS
                 const start = node.getStart() + astOffset;
                 const end = node.getEnd() + astOffset;
 
-                str.prependLeft(start, '() => {');
+                str.prependLeft(start, ';() => {');
                 str.prependRight(end, '}');
             }
         }

packages/svelte2tsx/test/sourcemaps/repl.html

@@ -62,7 +62,7 @@
 	});
 
     // TODO is there a non-hacky way to trigger scroll when chapter changes?
-    () => {$: if (scrollable) chapter, scrollable.scrollTo(0, 0);}
+    ;() => {$: if (scrollable) chapter, scrollable.scrollTo(0, 0);}
 
 	// TODO: this will need to be changed to the master branch, and probably should be dynamic instead of included
 	//   here statically
@@ -77,7 +77,7 @@
 		source: file.source
 	});
 
-    () => {$: if (repl) {
+    ;() => {$: if (repl) {
 		completed = false;
 		repl.set({
 			components: chapter.app_a.map(clone)

packages/svelte2tsx/test/svelte2tsx/samples/reactive-block/expected.tsx

@@ -1,7 +1,7 @@
 <></>;function render() {
 
 let a: 1 | 2 = 1;
-() => {$: {
+;() => {$: {
     console.log(a + 1);
 }}
 ;