Merge pull request #31378 from vespa-engine/bjorncs/user

Take overload taking existing instance

jdisc-security-filters/src/main/java/com/yahoo/jdisc/http/filter/security/misc/User.java

@@ -35,6 +35,7 @@ private User(Builder builder) {
     }
 
     public static Builder builder() { return new Builder(); }
+    public static Builder builder(User u) { return new Builder(u); }
 
     public static class Builder {
         private String email;
@@ -48,6 +49,17 @@ public static class Builder {
 
         private Builder() {}
 
+        private Builder(User u) {
+            email = u.email;
+            name = u.name;
+            nickname = u.nickname;
+            picture = u.picture;
+            isVerified = u.isVerified;
+            loginCount = u.loginCount;
+            lastLogin = u.lastLogin;
+            extraAttributes.putAll(u.extraAttributes);
+        }
+
         public Builder email(String email) { this.email = email; return this; }
         public Builder name(String name) { this.name = name; return this; }
         public Builder nickname(String nickname) { this.nickname = nickname; return this; }