🔨 Build scripts cleanup (#27157)

Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>

buildroot/share/PlatformIO/scripts/stm32_serialbuffer.py

@@ -3,7 +3,7 @@
 #
 import pioutil
 if pioutil.is_pio_build():
-    Import("env")
+    env = pioutil.env
 
     # Get a build flag's value or None
     def getBuildFlagValue(name):