strace: fix source tarball

The previous version was not the actual release, and was not supposed to
be published at all. This one is the signed release. Additionally,
upstream plans no more releases on sourceforge so the URL has been
changed to refer to strace.io instead.

pkgs/development/tools/misc/strace/default.nix

···
   version = "4.21";
 
   src = fetchurl {
-    url = "mirror://sourceforge/strace/${name}.tar.xz";
-    sha256 = "1dvrwi6v9j6b9j6852zzlc61hxgiciadi1xsl89wzbzqlkxnahbd";
+    url = "https://strace.io/files/${version}/${name}.tar.xz";
+    sha256 = "0dsw6xcfrmygidp1dj2ch8cl8icrar7789snkb2r8gh78kdqhxjw";
   };
 
   nativeBuildInputs = [ perl ];
···
   configureFlags = stdenv.lib.optional stdenv.hostPlatform.isAarch64 "--enable-mpers=check";
 
   meta = with stdenv.lib; {
-    homepage = http://strace.sourceforge.net/;
+    homepage = http://strace.io/;
     description = "A system call tracer for Linux";
     license = licenses.bsd3;
     platforms = platforms.linux;