Log Message:
poppler*: update to 21.05.0

Release 21.05.0:
        core:
         * Fix crashes in malformed files
         * Export SplashFont* symbols used by Scribus
         * Minor code improvements

        glib:
         * Enhance find to support multi-line matching

        qt5/qt6:
         * Make sure new signatures are always properly oriented
         * Allow to pass the border width when signing

        utils:
         * pdftoppm: Fix regression when using single scaleTo. Issue #1062

        build system:
         * Allow to disable building manual tests