Adjust fast forward for token expiration test (#30668)

Adjust fast forward for token expiration test

Adjusts the maximum fast forward time for token expiration tests
to be 5 seconds before actual token expiration so that the test
won't fail even when upperlimit is randomly selected.

Resolves: #30062

Author: jkakavas

x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/authc/TokenServiceTests.java

@@ -450,7 +450,7 @@ public void testTokenExpiry() throws Exception {
         }
 
         final TimeValue defaultExpiration = TokenService.TOKEN_EXPIRATION.get(Settings.EMPTY);
-        final int fastForwardAmount = randomIntBetween(1, Math.toIntExact(defaultExpiration.getSeconds()));
+        final int fastForwardAmount = randomIntBetween(1, Math.toIntExact(defaultExpiration.getSeconds()) - 5);
         try (ThreadContext.StoredContext ignore = requestContext.newStoredContext(true)) {
             // move the clock forward but don't go to expiry
             clock.fastForwardSeconds(fastForwardAmount);