[feat][ws] Use async auth method to support OIDC (apache#20238)

Fixes apache#20236
PIP: apache#19409

### Motivation

In the `AuthenticationService`, we are currently using the deprecated `authenticate` methods. As a result, we hit the `Not Implemented` exception when using the `AuthenticationProviderOpenID`. This PR updates the implementation so that we're able

This solution isn't ideal for two reasons.

1. We are not using the `authenticationHttpRequest` method, which seems like the right method for the WebSocket proxy. However, this is not a viable option, as I documented in apache#20237.
2. We are calling `.get()` on a future. However, it is expected that the `AuthenticationProvider` not block forever, so I think this is acceptable for now. Please let me know if you disagree.

### Modifications

* Replace `authenticate` with `authenticateAsync`.

### Verifying this change

This change is a trivial rework / code cleanup without any test coverage.

### Documentation

- [x] `doc-not-needed`

Note that I do have documentation showing that 3.0.x does not support OIDC in the WebSocket Proxy. The `next` docs don't need that limitation since this PR fixes that and targets 3.1.0. apache/pulsar-site#558

### Matching PR in forked repository

PR in forked repository: skipping for this trivial PR

(cherry picked from commit 03dc3db)

pulsar-broker-common/src/main/java/org/apache/pulsar/broker/authentication/AuthenticationService.java

@@ -27,6 +27,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.concurrent.ExecutionException;
 import java.util.stream.Collectors;
 import javax.naming.AuthenticationException;
 import javax.servlet.http.HttpServletRequest;
@@ -171,20 +172,26 @@ public String authenticateHttpRequest(HttpServletRequest request, Authentication
                     authData = authenticationState.getAuthDataSource();
                 }
                 // Backward compatible, the authData value was null in the previous implementation
-                return providerToUse.authenticate(authData);
+                return providerToUse.authenticateAsync(authData).get();
             } catch (AuthenticationException e) {
                 if (LOG.isDebugEnabled()) {
                     LOG.debug("Authentication failed for provider " + providerToUse.getAuthMethodName() + " : "
                             + e.getMessage(), e);
                 }
                 throw e;
+            } catch (ExecutionException | InterruptedException e) {
+                if (LOG.isDebugEnabled()) {
+                    LOG.debug("Authentication failed for provider " + providerToUse.getAuthMethodName() + " : "
+                            + e.getMessage(), e);
+                }
+                throw new RuntimeException(e);
             }
         } else {
             for (AuthenticationProvider provider : providers.values()) {
                 try {
                     AuthenticationState authenticationState = provider.newHttpAuthState(request);
-                    return provider.authenticate(authenticationState.getAuthDataSource());
-                } catch (AuthenticationException e) {
+                    return provider.authenticateAsync(authenticationState.getAuthDataSource()).get();
+                } catch (ExecutionException | InterruptedException | AuthenticationException e) {
                     if (LOG.isDebugEnabled()) {
                         LOG.debug("Authentication failed for provider " + provider.getAuthMethodName() + ": "
                                 + e.getMessage(), e);