app/tests: Drop dangling create_test_env.sh

Before the "fix" on 941fc000, everything was working fine, which
is a sign that it wasn't even being used. Also, after Jehan own
investigation and my tests, I confirmed that it isn't used anymore.

app/tests/create_test_env.sh

@@ -1,29 +0,0 @@
-#!/usr/bin/env sh
-
-# Copy tests resources
-for dir in files gimpdir gimpdir-empty; do
-    rm -rf "${MESON_BUILD_ROOT}/${MESON_SUBDIR}/${dir}"
-    cp -r "${MESON_SOURCE_ROOT}/${MESON_SUBDIR}/${dir}" \
-        "${MESON_BUILD_ROOT}/${MESON_SUBDIR}"
-done
-
-# Link to Color icon theme for tests
-IconsRoot="${MESON_SOURCE_ROOT}/gimp-data/icons/Default"
-IconsDirs=$(find "${IconsRoot}" -name [0-9]* -type d -printf '%f\n' | sort -n)
-for dir in ${IconsDirs} ; do
-    mkdir  "${MESON_BUILD_ROOT}/${MESON_SUBDIR}/gimp-test-icon-theme/hicolor/${dir}x${dir}" -p
-    LnName="${MESON_BUILD_ROOT}/${MESON_SUBDIR}/gimp-test-icon-theme/hicolor/${dir}x${dir}/apps"
-    rm -rf "${LnName}"
-    ln -s "${IconsRoot}/${dir}" "${LnName}"
-done
-
-LnName="${MESON_BUILD_ROOT}/${MESON_SUBDIR}/gimp-test-icon-theme/hicolor/index.theme"
-rm -rf "${LnName}"
-ln -s "${IconsRoot}/index.theme" "${LnName}"
-
-
-# Create output dirs
-rm -rf "${MESON_BUILD_ROOT}/${MESON_SUBDIR}/gimpdir-output"
-for dir in brushes gradients patterns; do
-    mkdir -p "${MESON_BUILD_ROOT}/${MESON_SUBDIR}/gimpdir-output/${dir}"
-done

app/tests/meson.build

@@ -44,11 +44,6 @@ app_tests = [
   'xcf',
 ]
 
-cmd = run_command('create_test_env.sh', check: false)
-if cmd.returncode() != 0
- error(cmd.stderr().strip())
-endif
-
 # Prevent parallel builds for the tests
 # The tests must not be run in parallel or in a different order as specified