Fix confusion about IDE breaking changes

Closed issue microsoft#994 (and presumably others) indicate that the confusing version text referring to 1.8.7 will be corrected, but that never happened.  This PR attempts to improve the text to correct the issue.

Author: mikebaz

README.md

@@ -22,7 +22,7 @@ Either the Arduino IDE or Arduino CLI are required.
 The Arduino IDE can be installed the Arduino [download page](https://www.arduino.cc/en/main/software#download).
 - The supported Arduino IDE versions are `1.6.x` and later.
 - The Windows Store's version of the Arduino IDE is not supported because of the sandbox environment that the application runs in.
-- *Note:* Arduino IDE `1.8.7` has some breaking changes, causing board package and library installation failures.
+- *Note:* Arduino IDE `1.8.7` had some breaking changes, causing board package and library installation failures.  These failures were corrected in `1.8.8` and later.
 
 ### Arduino CLI
 The Arduino CLI can be downloaded from the repository's [release page](https://github.com/arduino/arduino-cli/releases/tag/0.13.0)