Always exclude range test

Range test is excluded on every target as of 2.8, so set
MESHTASTIC_EXCLUDE_RANGETEST=1 globally in [env] build_flags and drop the
now-redundant per-variant flags from esp32, rak11200 and stm32.

Guard RangeTestModule.cpp with the same condition used in Modules.cpp so the
translation unit compiles to nothing rather than relying on --gc-sections to
strip it, and always report RANGETEST_CONFIG in the device metadata
excluded_modules bitmask so clients hide the config.

variants/esp32/esp32.ini

@@ -19,7 +19,6 @@ build_flags =
   -DMESHTASTIC_EXCLUDE_ACCELEROMETER=1
   -DMESHTASTIC_EXCLUDE_PAXCOUNTER=1
   -DMESHTASTIC_EXCLUDE_WEBSERVER=1
-  -DMESHTASTIC_EXCLUDE_RANGETEST=1
   ; HACK HACK HACK this is just a proof of concept ESP32+NimBLE but these
   ; includes need to be done properly somehow
   ; Quotes keep Windows packages_dir backslashes intact through POSIX flag parsing

variants/esp32/rak11200/platformio.ini

@@ -18,6 +18,5 @@ build_flags =
   -I variants/esp32/rak11200
   -DMESHTASTIC_EXCLUDE_WEBSERVER=1
   -DMESHTASTIC_EXCLUDE_PAXCOUNTER=1
-  -DMESHTASTIC_EXCLUDE_RANGETEST=1
   -DMESHTASTIC_EXCLUDE_MQTT=1
 upload_speed = 115200