[hal] Add high level way of getting systemserver NT instance (#7683)

wpilibj/src/main/java/edu/wpi/first/wpilibj/SystemServer.java

@@ -0,0 +1,23 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+package edu.wpi.first.wpilibj;
+
+import edu.wpi.first.hal.SystemServerJNI;
+import edu.wpi.first.networktables.NetworkTableInstance;
+
+/** Class to get system server NT instance. */
+public final class SystemServer {
+  /**
+   * Gets the system server NT Instance.
+   *
+   * @return NT Instance
+   */
+  public static NetworkTableInstance getSystemServer() {
+    return NetworkTableInstance.fromNativeHandle(SystemServerJNI.getSystemServerHandle());
+  }
+
+  /** Utility Class. */
+  private SystemServer() {}
+}