[Backport staging-26.05] git: fix interpreter paths in contrib scripts (#563192)

pkgs/by-name/gi/git/package.nix

@@ -85,6 +85,11 @@ let
     AuthenSASL
     DigestHMAC
   ];
+  gitJumpBinPath = lib.makeBinPath [
+    "$out"
+    perlPackages.perl
+    coreutils
+  ];
 in
 
 stdenv.mkDerivation (finalAttrs: {
@@ -207,6 +212,7 @@ stdenv.mkDerivation (finalAttrs: {
     (if stdenv.hostPlatform.isFreeBSD then libiconvReal else libiconv)
     bash
   ]
+  ++ lib.optionals pythonSupport [ python3 ]
   ++ lib.optionals perlSupport [ perlPackages.perl ]
   ++ lib.optionals guiSupport [
     tcl
@@ -393,9 +399,11 @@ stdenv.mkDerivation (finalAttrs: {
     # Also put git-http-backend into $PATH, so that we can use smart
     # HTTP(s) transports for pushing
     ln -s $out/libexec/git-core/git-http-backend${stdenv.hostPlatform.extensions.executable} $out/bin/git-http-backend
-    ln -s $out/share/git/contrib/git-jump/git-jump $out/bin/git-jump
   ''
   + lib.optionalString perlSupport ''
+    makeWrapper $out/share/git/contrib/git-jump/git-jump $out/bin/git-jump \
+      --prefix PATH : "${gitJumpBinPath}"
+
     # wrap perl commands
     makeWrapper "$out/share/git/contrib/credential/netrc/git-credential-netrc.perl" $out/libexec/git-core/git-credential-netrc \
                 --set PERL5LIB   "$out/${perlPackages.perl.libPrefix}:${perlPackages.makePerlPath perlLibs}"
@@ -422,6 +430,10 @@ stdenv.mkDerivation (finalAttrs: {
     done
   ''
 
+  + lib.optionalString pythonSupport ''
+    patchShebangs $out/share/git/contrib/fast-import/import-zips.py
+  ''
+
   + (
     if svnSupport then
       ''