[release] change version to 0.4.0 without dev

Author: rhdong

tensorflow_recommenders_addons/version.py

@@ -30,7 +30,7 @@
 # stable release (indicated by `_VERSION_SUFFIX = ''`). Outside the context of a
 # release branch, the current version is by default assumed to be a
 # 'development' version, labeled 'dev'.
-_VERSION_SUFFIX = "dev"
+_VERSION_SUFFIX = ""
 
 # Example, '0.1.0-dev'
 __version__ = ".".join([_MAJOR_VERSION, _MINOR_VERSION, _PATCH_VERSION])