Fix build of breeze-gtk2

Author: bbhtt

gtk2/gtk2-common-themes.json

@@ -147,7 +147,7 @@
             "buildsystem": "simple",
             "build-commands": [
                 "find breeze-gtk/src -name '*.scss' -print -execdir sed -i 's#\\.\\./assets/#./assets/#' {} \\;",
-                "cd breeze-gtk/src && sed -i 's/@PYTHON_EXECUTABLE@/python3/g' build_theme.sh.cmake && ./build_theme.sh.cmake -c BreezeLight -t ${FLATPAK_BUILDER_BUILDDIR}/Breeze -r ${FLATPAK_BUILDER_BUILDDIR}/breeze/colors",
+                "cd breeze-gtk/src && sed -i 's/@Python3_EXECUTABLE@/python3/g' build_theme.sh.cmake && ./build_theme.sh.cmake -c BreezeLight -t ${FLATPAK_BUILDER_BUILDDIR}/Breeze -r ${FLATPAK_BUILDER_BUILDDIR}/breeze/colors",
                 "mkdir -p ${FLATPAK_DEST}/share/themes/Breeze/",
                 "cp -rv --no-preserve=ownership ${FLATPAK_BUILDER_BUILDDIR}/Breeze/gtk-2.0 ${FLATPAK_DEST}/share/themes/Breeze/",
                 "cp -rv --no-preserve=ownership ${FLATPAK_BUILDER_BUILDDIR}/Breeze/assets ${FLATPAK_DEST}/share/themes/Breeze/"