update return type for AuthCheck and SuspenseWithPerf to JSX.Element (#162)

* update return type for AuthCheck and SuspenseWithPerf to JSX.Element

* remove changes to yarn.lock

* wrap AuthCheck fallback and children in React Fragment

* fix brackets

Author: seanemmer

reactfire/auth/index.tsx

@@ -92,7 +92,7 @@ export function AuthCheck({
   fallback,
   children,
   requiredClaims
-}: AuthCheckProps): React.ReactNode {
+}: AuthCheckProps): JSX.Element {
   const user = useUser<User>(auth);
 
   if (user) {
@@ -105,9 +105,9 @@ export function AuthCheck({
         {children}
       </ClaimsCheck>
     ) : (
-      children
+      <>{children}</>
     );
   } else {
-    return fallback;
+    return <>{fallback}</>;
   }
 }

reactfire/performance/index.tsx

@@ -33,7 +33,7 @@ export function SuspenseWithPerf({
   traceId,
   fallback,
   firePerf
-}: SuspensePerfProps) {
+}: SuspensePerfProps): JSX.Element {
   firePerf = firePerf || getPerfFromContext();
 
   const Fallback = () => {