Fix baselines after bad merge (microsoft#53546)

Author: jakebailey

tests/baselines/reference/declarationEmitLateBoundJSAssignments.js

@@ -25,6 +25,6 @@ const a = foo[dashStrMem];
 //// [file.d.ts]
 export function foo(): void;
 export namespace foo {
-    const bar: number;
-    const strMemName: string;
+    let bar: number;
+    let strMemName: string;
 }