Revert "update cmake_minimum_required to 3.21.0"

JojoS62 · JojoS62 · commit 750247c47200 · 2021-10-05T17:16:59.000+02:00
This reverts commit cfa8865.
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -3,7 +3,7 @@
 
 # This is the boilerplate for Mbed OS
 
-cmake_minimum_required(VERSION 3.21.0 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.19.0 FATAL_ERROR)
 
 option(BUILD_GREENTEA_TESTS "Build greentea tests only." OFF)
 
