Bump version to 5.2.2

HISTORY.rst

@@ -8,10 +8,11 @@ PlatformIO Core 5
 
 **A professional collaborative platform for embedded development**
 
-5.2.2 (2021-??-??)
+5.2.2 (2021-10-20)
 ~~~~~~~~~~~~~~~~~~
 
 - Override debugging firmware loading mode using ``--load-mode`` option for `pio debug <https://docs.platformio.org/en/latest/core/userguide/cmd_debug.html>`__ command
+- Added support for CLion IDE 2021.3 (`pull #4085 <https://github.com/platformio/platformio-core/issues/4085>`_)
 - Removed debugging "legacy Click" message from CLI (`issue #4083 <https://github.com/platformio/platformio-core/issues/4083>`_)
 - Fixed a "TypeError: sequence item 1: expected str instance, list found" issue when extending configuration option in `"platformio.ini" <https://docs.platformio.org/page/projectconf.html>`__ with the multi-line default value (`issue #4082 <https://github.com/platformio/platformio-core/issues/4082>`_)
 

platformio/__init__.py

@@ -14,7 +14,7 @@
 
 import sys
 
-VERSION = (5, 2, "2a1")
+VERSION = (5, 2, 2)
 __version__ = ".".join([str(s) for s in VERSION])
 
 __title__ = "platformio"