Skip FIPS JVMs in `testReloadCredentialsFromKeystore`

This test doesn't need to run in FIPS mode, and apparently it fails
sometimes, so with this commit we skip it.

Closes #116811
Backport of #116814 to 8.x

modules/repository-s3/src/javaRestTest/java/org/elasticsearch/repositories/s3/RepositoryS3RestIT.java

@@ -51,8 +51,9 @@ public class RepositoryS3RestIT extends ESRestTestCase {
         return cluster.getHttpAddresses();
     }
 
-    @AwaitsFix(bugUrl = "https://github.com/elastic/elasticsearch/issues/116811")
     public void testReloadCredentialsFromKeystore() throws IOException {
+        assumeFalse("doesn't work in a FIPS JVM, but that's ok", inFipsJvm());
+
         // Register repository (?verify=false because we don't have access to the blob store yet)
         final var repositoryName = randomIdentifier();
         registerRepository(