frontend: Fix refreshToken

the token expiry check in refreshToken was failing
when the decodeToken returned null.this patch adds
a check to see if the decodedToken exists before
accessing the .exp property

Signed-off-by: yolossn <sannagaraj@microsoft.com>

frontend/src/lib/k8s/apiProxy.ts

@@ -208,7 +208,7 @@ async function refreshToken(token: string | null): Promise<void> {
   const decodedToken: any = decodeToken(token);
 
   // return if the token doesn't have an expiry time
-  if (!decodedToken.exp) {
+  if (!decodedToken?.exp) {
     return;
   }
   // convert expiry seconds to date object