Remove mypy check

Unfortunately, the mypy check has been rotting for years now. Let's not
pretend like this check is maintained and remove the associated code.

.gitlab-ci.yml

@@ -11,11 +11,6 @@ stages:
     - linux
     - amd64
 
-test:mypy:
-  <<: *debian
-  script:
-    - ./ci/mypy-run.sh
-
 test:flake8:
   <<: *debian
   script:

ci/mypy-run.sh

-#!/usr/bin/env bash
-set -e
-
-# Find Python scripts
-FILES=$(find . \
-	-path './ci' -prune -o \
-	-path './.git' -prune -o \
-	-name '*.py' -print)
-
-python3 -m mypy --install-types --non-interactive --ignore-missing-imports ${FILES}