[gobject-introspection] CI: pin mypy for now

[Christoph Reiter <creiter src gnome org>]

commit 7352b59dd32db47f336b8aad474cdaa024ca2580
Author: Christoph Reiter <reiter christoph gmail com>
Date:   Mon Jan 25 10:30:13 2021 +0100

    CI: pin mypy for now
    
    The latest release (0.800) finds a handful of new problems that need
    to be addressed first.

 .gitlab-ci.yml                 | 2 +-
 .gitlab-ci/test-msys2-meson.sh | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 55c320c9..10124cb5 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -56,7 +56,7 @@ fedora-x86_64-meson:
     - cd ..
     - mkdir -p public
     - mv _build/docs/reference/html/ public/girepository/
-    - python3 -m pip install --user flake8 mypy
+    - python3 -m pip install --user flake8 mypy==0.790
     - python3 -m flake8 --count
     - python3 -m mypy .
   except:
diff --git a/.gitlab-ci/test-msys2-meson.sh b/.gitlab-ci/test-msys2-meson.sh
index 81a82437..56f8c9b3 100644
--- a/.gitlab-ci/test-msys2-meson.sh
+++ b/.gitlab-ci/test-msys2-meson.sh
@@ -31,7 +31,7 @@ pacman --noconfirm -S --needed \
 export CCACHE_BASEDIR="${CI_PROJECT_DIR}"
 export CCACHE_DIR="${CCACHE_BASEDIR}/_ccache"
 
-pip3 install --upgrade --user meson==0.50.1 flake8 mypy
+pip3 install --upgrade --user meson==0.50.1 flake8 mypy==0.790
 export PATH="$HOME/.local/bin:$PATH"
 
 export CFLAGS="-Werror"