treewide: homepage+src updates (found by repology, #33263)

pkgs/data/documentation/zeal/default.nix

@@ -32,7 +32,7 @@ stdenv.mkDerivation rec {
       Zeal is a simple offline API documentation browser inspired by Dash (macOS
       app), available for Linux and Windows.
     '';
-    homepage    = http://zealdocs.org/;
+    homepage    = https://zealdocs.org/;
     license     = licenses.gpl3;
     maintainers = with maintainers; [ skeidel peterhoeg ];
     platforms   = platforms.linux;

pkgs/data/fonts/gentium/default.nix

@@ -18,7 +18,7 @@ in fetchzip rec {
   sha256 = "1qr2wjdmm93167b0w9cidlf3wwsyjx4838ja9jmm4jkyian5whhp";
 
   meta = with stdenv.lib; {
-    homepage = http://software.sil.org/gentium/;
+    homepage = https://software.sil.org/gentium/;
     description = "A high-quality typeface family for Latin, Cyrillic, and Greek";
     longDescription = ''
       Gentium is a typeface family designed to enable the diverse ethnic groups
@@ -35,7 +35,7 @@ in fetchzip rec {
       This package contains the regular and italic styles for the Gentium Plus
       font family, along with documentation.
     '';
-    downloadPage = "http://software.sil.org/gentium/download/";
+    downloadPage = "https://software.sil.org/gentium/download/";
     maintainers = with maintainers; [ raskin rycee ];
     license = licenses.ofl;
     platforms = platforms.all;

pkgs/data/fonts/open-dyslexic/default.nix

@@ -16,7 +16,7 @@ in fetchzip {
   sha256 = "045xc7kj56q4ygnjppm8f8fwqqvf21x1piabm4nh8hwgly42a3w2";
 
   meta = with stdenv.lib; {
-    homepage = http://opendyslexic.org/;
+    homepage = https://opendyslexic.org/;
     description = "Font created to increase readability for readers with dyslexia";
     license = "Bitstream Vera License (https://www.gnome.org/fonts/#Final_Bitstream_Vera_Fonts)";
     platforms = platforms.all;