@Test
    public void resolve_FileBase64() throws Exception {
        String input = getPath("secret.json").toAbsolutePath().toString();
        String output = resolve("${base64:${readFile:" + input + "}}");
        String decoded = DECODE.lookup(output);
        String content = FILE.lookup(input);
        assertThat(output, equalTo(ENCODE.lookup(content)));
        assertThat(decoded, equalTo(content));
        assertThat(decoded, containsString("\"Our secret\": \"Hello World\""));
    }
Ensures that prefixes in the secret ID which are not covered by the CasC protocol substitutors (e.g. base64:, file:)
are left untouched and not removed.
plugin/src/test/java/io/jenkins/plugins/casc/SecretSourceResolverTest.java