chore: update versions for 0.4.0

Author: paleolimbot

Diff for: CMakeLists.txt

@@ -22,7 +22,7 @@ if(NOT DEFINED CMAKE_C_STANDARD)
   set(CMAKE_C_STANDARD 99)
 endif()
 
-set(NANOARROW_VERSION "0.4.0-SNAPSHOT")
+set(NANOARROW_VERSION "0.4.0")
 string(REGEX MATCH "^[0-9]+\\.[0-9]+\\.[0-9]+" NANOARROW_BASE_VERSION
              "${NANOARROW_VERSION}")
 project(nanoarrow VERSION "${NANOARROW_BASE_VERSION}")

Diff for: python/src/nanoarrow/_static_version.py

@@ -18,7 +18,7 @@
 # This file is part of 'miniver': https://github.com/jbweston/miniver
 
 # Replaced by version-bumping scripts at release time
-version = "0.4.0.dev0"
+version = "0.4.0"
 
 # These values are only set if the distribution was created with 'git archive'
 refnames = "$Format:%D$"

Diff for: r/DESCRIPTION

@@ -1,6 +1,6 @@
 Package: nanoarrow
 Title: Interface to the 'nanoarrow' 'C' Library
-Version: 0.3.0.9000
+Version: 0.4.0
 Authors@R: c(
     person(given = "Dewey",
            family = "Dunnington",