Add checkPhase for yosys tests

flake.nix

@@ -30,6 +30,9 @@
 					buildPhase = ''
             make -j$(nproc) ABCEXTERNAL=yosys-abc
           '';
+          checkPhase = ''
+          make test
+          '';
           meta = with pkgs.lib; {
             description = "Yosys Open SYnthesis Suite";
             homepage = "https://yosyshq.net/yosys/";
@@ -39,8 +42,7 @@
         };
       in {
         packages.default = yosys;
-        defaultPackage = yosys;
-        devShell = pkgs.mkShell {
+        devShells.default = pkgs.mkShell {
           buildInputs = with pkgs; [ clang bison flex libffi tcl readline python3 llvmPackages.libcxxClang zlib git gtest abc-verifier ];
           LOCALE_ARCHIVE = "${pkgs.glibcLocales}/lib/locale/locale-archive";
         };