The logic for the cache in `JwtRealm` produces a broken `Cache` instance to some degree. 
We create a `BytesArray` from the user credential hash:

```java
            final BytesArray jwtCacheKey = isCacheEnabled() ? new BytesArray(jwtAuthenticationToken.getUserCredentialsHash()) : null;
            if (jwtCacheKey != null) {
                final User cachedUser = tryAuthenticateWithCache(tokenPrincipal, jwtCacheKey);
```

and use it as as a cache key in a `Cache` instance down the line.
But then we also clear the bytes in that `BytesArray` to `0` in org.elasticsearch.xpack.security.authc.jwt.JwtAuthenticationToken#clearCredentials. 

This leads to the hash map in the `Cache` getting filled with loads of `BytesArray` that all have the same 0-filled content but that were not equal to each other when first inserted into the map, causing the map to put them all in the same bucket.

<img width="1233" alt="image" src="https://github.com/elastic/elasticsearch/assets/6490959/86a914d7-a2d4-4b01-ad99-e0d14e71a58b">

ref path to the broken map:

<img width="1436" alt="image" src="https://github.com/elastic/elasticsearch/assets/6490959/87ac6f78-bc09-41c4-9a79-28fbbd14f6e6">

x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/jwt/JwtRealm.java
name(),
                cacheEntryNotExpired ? "hit" : "exp",
                tokenPrincipal,
                jwtCacheKey,
                principal,
                exp,
                now
            );
            if (cacheEntryNotExpired) {
                return user;
            }
            
        }
        return null;
    }
    
    void processValidatedJwt(
        String tokenPrincipal,
        BytesArray jwtCacheKey,
        JWTClaimsSet claimsSet,
        ActionListener<AuthenticationResult<User>> listener
    ) {
        
        final String principal = claimParserPrincipal.getClaimValue(claimsSet);
        if (Strings.hasText(principal) == false) {
            final String msg = "Realm ["
                + name()
                + "] no principal for token=["
                + tokenPrincipal
                + "] parser=["