temp/gtk+3.0: upgrade to latest Purism version (MR 1810)

[ci:skip-build]: already built successfully in CI

temp/gtk+3.0/APKBUILD

 # Forked from Alpine to apply Purism's patches for responsivness
 pkgname=gtk+3.0
-pkgver=9999_git20201022
+pkgver=9999_git20201211
 pkgrel=0
-_commit="a3994f140fe20c0bc7c6cd13a60cdf9700461a94"
+_commit="dd1aa3de371d618707473d4ffb5986cc5896ed2f"
 pkgdesc="The GTK+ Toolkit (v3)"
 url="https://www.gtk.org/"
 install="$pkgname.post-install $pkgname.post-upgrade $pkgname.post-deinstall"
@@ -136,5 +136,5 @@ doc() {
 	default_doc
 }
 
-sha512sums="bd573a5d48b5621cb243418f6bb9a5b2954e218d7955f7acb1a340c8b67f363bb1c4fcde24fa7e5314a557aaa00e5e0fb7d6b8d3ffbf79da733c0ce422c608ec  gtk-a3994f140fe20c0bc7c6cd13a60cdf9700461a94.tar.gz
+sha512sums="f795f2896ccdbc87291ecdc7b1884f046e1916445f1c98087f6a5fb43d848b20602d4594a9838c9fe3982a0da04c04da2136f9bd8b74d0f4a9c41581499c9a53  gtk-dd1aa3de371d618707473d4ffb5986cc5896ed2f.tar.gz
 b97ccd8fb78d7c32fe91607befd6a7c0dd969fbfc9c242948fc88085133e3461583a0b18ade199b73f9659cae5f5525b940e66535a6ced4b916af9a88b3cc578  check-version.py"