Update core modules to stable versions

requirements/core_modules.txt

@@ -1,6 +1,6 @@
 # neon core modules
 neon_messagebus~=2.0,>=2.0.1
 neon_enclosure~=1.7
-neon_speech~=4.3,>=4.3.1a7
+neon_speech~=4.4
 neon_gui~=1.3
 neon_audio~=1.5,>=1.5.1