@Test
    public void readFirstSecretPathWithCli() throws Exception {
        GenericContainer.ExecResult result = vaultContainer.execInContainer(
            "vault",
            "kv",
            "get",
            "-format=json",
            "secret/testing1"
        );
        assertThat(result.getStdout()).contains("password123");
    }
This test shows the pattern to use the VaultContainer @ClassRule for a junit test. It also has tests that ensure
the secrets were added correctly by reading from Vault with the CLI, over HTTP and over Client Library.
modules/vault/src/test/java/org/testcontainers/vault/VaultContainerTest.java