replace regex match with simple string comparisons

Signed-off-by: Ludovic Orban <lorban@bitronix.be>

jetty-client/src/main/java/org/eclipse/jetty/client/HttpClient.java

@@ -1145,7 +1145,7 @@ public class HttpClient extends ContainerLifeCycle
 
     protected String normalizeHost(String host)
     {
-        if (host != null && host.matches("\\[.*\\]"))
+        if (host != null && host.startsWith("[") && host.endsWith("]"))
             return host.substring(1, host.length() - 1);
         return host;
     }