### CI Link

https://gradle-enterprise.elastic.co/s/jze725jpxi7ki/console-log?task=:x-pack:plugin:security:internalClusterTest

### Repro line

./gradlew ':x-pack:plugin:security:internalClusterTest' --tests "org.elasticsearch.xpack.security.authc.pki.PkiAuthDelegationIntegTests.testDelegateThenAuthenticate" -Dtests.seed=F5EC1FEFFC2FC08B -Dtests.locale=en-GB -Dtests.timezone=SystemV/PST8PDT -Druntime.java=20

### Does it reproduce?

Yes

### Applicable branches

main

### Failure history

_No response_

### Failure excerpt

The pki integ test began failing today. Looking at the certs the test uses, they are all expired:

```
❯ openssl x509 -enddate -noout -in testClient.crt
notAfter=Jul 18 13:33:41 2023 GMT
❯ openssl x509 -enddate -noout -in testIntermediateCA.crt
notAfter=Jul 18 13:32:34 2023 GMT
❯ openssl x509 -enddate -noout -in testRootCA.crt
notAfter=Jul 18 13:32:20 2023 GMT
```
x-pack/plugin/security/src/internalClusterTest/java/org/elasticsearch/xpack/security/authc/pki/PkiAuthDelegationIntegTests.java
basicAuthHeaderValue(delegateeUsername, SecuritySettingsSourceField.TEST_PASSWORD_SECURE_STRING)
            );
            var delegatePkiResponse = getSecurityClient(optionsBuilder.build()).delegatePkiAuthentication(certificateChain);
            String token = delegatePkiResponse.v1();
            assertThat(token, is(notNullValue()));
            assertNotNull(delegatePkiResponse.v2());
            final Map<String, Object> authentication = assertMap(delegatePkiResponse.v2(), AUTHENTICATION_FIELD);
            assertThat(authentication, hasEntry(Fields.USERNAME.getPreferredName(), "Elasticsearch Test Client"));
            
            optionsBuilder = RequestOptions.DEFAULT.toBuilder();
            optionsBuilder.addHeader("Authorization", "Bearer " + token);
            final TestSecurityClient securityClient = getSecurityClient(optionsBuilder.build());
            final Map<String, Object> authenticateResponse = securityClient.authenticate();
            assertThat(authenticateResponse, hasEntry(Fields.USERNAME.getPreferredName(), "Elasticsearch Test Client"));
            Map<String, Object> realm = assertMap(authenticateResponse, Fields.AUTHENTICATION_REALM);
            assertThat(realm, hasEntry(Fields.REALM_NAME.getPreferredName(), "pki3"));
            assertThat(realm, hasEntry(Fields.REALM_TYPE.getPreferredName(), "pki"));
            assertThat(authenticateResponse, hasEntry(Fields.AUTHENTICATION_TYPE.getPreferredName(), "token"));
        }
    }
    @AwaitsFix(bugUrl = "https://github.com/elastic/elasticsearch/issues/97772")
    public void testTokenInvalidate() throws Exception {
        final X509Certificate clientCertificate = readCertForPkiDelegation("testClient.crt");
        final X509Certificate intermediateCA = readCertForPkiDelegation("testIntermediateCA.crt");
        final X509Certificate rootCA = readCertForPkiDelegation("testRootCA.crt");
        final List<X509Certificate> certificateChain;
        
        if (randomBoolean()) {
            certificateChain = List.of(clientCertificate, intermediateCA);
        } else {