switch to official DelaunayNim URL (nim-lang#21269)

follow up Nycto/DelaunayNim#4 (comment)

Author: ringabout

testament/important_packages.nim

@@ -60,7 +60,7 @@ pkg "comprehension", "nimble test", "https://github.com/alehander92/comprehensio
 pkg "criterion", allowFailure = true # pending https://github.com/disruptek/criterion/issues/3 (wrongly closed)
 pkg "datamancer"
 pkg "dashing", "nim c tests/functional.nim"
-pkg "delaunay", url = "https://github.com/nim-lang/DelaunayNim", useHead = true
+pkg "delaunay"
 pkg "docopt"
 pkg "easygl", "nim c -o:egl -r src/easygl.nim", "https://github.com/jackmott/easygl"
 pkg "elvis"