Add note indicating the data log feature was added in 2022.4.1 (#1771)

Author: PeterJohnson

source/docs/software/telemetry/datalog.rst

@@ -1,6 +1,8 @@
 On-Robot Telemetry Recording Into Data Logs
 ===========================================
 
+.. note:: The DataLog feature and Data Log Tool were added in WPILib 2022.4.1. The Data Log Tool is installed by the WPILib installer only (new tools are not installed when a robot project is upgraded).
+
 By default, no telemetry data is recorded (saved) on the robot. The ``DataLogManager`` class provides a convenient wrapper around the lower-level ``DataLog`` class for on-robot recording of telemetry data into data logs.  The WPILib data logs are binary for size and speed reasons.  In general, the data log facilities provided by WPILib have minimal overhead to robot code, as all file I/O is performed on a separate thread--the log operation consists of mainly a mutex acquisition and copying the data.
 
 Structure of Data Logs