nixpkgs-basic-release-checks: check for use of url literals

Nixpkgs should not rely on that deprecated feature.

pkgs/top-level/nixpkgs-basic-release-checks.nix

@@ -36,6 +36,7 @@ pkgs.runCommand "nixpkgs-release-checks" { src = nixpkgs; buildInputs = [nix]; }
         nix-env -f $src \
             --show-trace --argstr system "$platform" \
             --arg config '{ allowAliases = false; }' \
+            --option experimental-features 'no-url-literals' \
             -qa --drv-path --system-filter \* --system \
             "''${opts[@]}" 2>&1 >/dev/null | tee eval-warnings.log
 
@@ -48,6 +49,7 @@ pkgs.runCommand "nixpkgs-release-checks" { src = nixpkgs; buildInputs = [nix]; }
         nix-env -f $src \
             --show-trace --argstr system "$platform" \
             --arg config '{ allowAliases = false; }' \
+            --option experimental-features 'no-url-literals' \
             -qa --drv-path --system-filter \* --system --meta --xml \
             "''${opts[@]}" > /dev/null
     done