[E2E Enhancement] more E2E cases for applications outside of Mesh

[YaoZengzeng]

What would you like to be added:

Now all applications in the E2E tests, whether client or server, are managed by the Kmesh (https://github.com/kmesh-net/kmesh/blob/main/test/e2e/main_test.go#L132). We should add applications that are not managed by the Kmesh to test whether the access between the two meets expectations.

Why is this needed:

In production env, there will be services outside of Mesh accessing services inside the Mesh and there will also be services inside the Mesh accessing services outside the Mesh.