Merge pull request #248468 from cmoog/write-shell-script-main-program

trivial-builders: add meta.mainProgram to writeShellScriptBin

pkgs/build-support/trivial-builders/default.nix

···
       checkPhase = ''
         ${stdenv.shellDryRun} "$target"
       '';
+      meta.mainProgram = name;
     };
 
   /*