[vala] Created tag 0.48.21

[Rico Tzschichholz <ricotz src gnome org>]

The signed tag '0.48.21' was created.

Tagger: Rico Tzschichholz <ricotz ubuntu com>
Date: 1641668057 +0100

    0.48.21

Changes since the last tag '0.48.20':

Rico Tzschichholz (9):
      vala: Allow unsafe assignment of integer to enum while reporting a notice
      vala: Non nullable enum types are simple types
      vala: Correctly replace "in" expression in pre-/postconditions of method
      gio-2.0: Add custom MemoryOutputStream.with_*data() wrappers
      codegen: Allow boxing of non-external SimpleType structs
      codegen: Cast given default-value of struct with possible member initializer
      tests: Add "async signal handler" test to increase coverage
      codegen: Clear existing length values when revisiting a slice expression
      Release 0.48.21