buildGleam: adapt to gleam2nix changes

nix/build-gleam.nix

···
     configurePhase = ''
       runHook preConfigure
 
-      mkdir lib
-      ${lib.concatMapStringsSep "\n" (package: "ln -s ${package}/lib/erlang/lib/* lib/") beamDeps}
+      mkdir deps
+      ${lib.concatMapStringsSep "\n" (package: "ln -s ${package}/lib/erlang/lib/* deps/") beamDeps}
 
       runHook postConfigure
     '';
···
     buildPhase = ''
       runHook preBuild
 
-      gleam compile-package --target erlang --package . --lib lib --out build
+      gleam compile-package --target erlang --package . --lib deps --out build
 
-      gleam2nix gen-app -n ${name} -v ${version} ${
-        lib.concatMapStringsSep " " (dep: "-d ${dep.otpApplication}") beamDeps
-      } build/ebin
+      gleam2nix appspec build/ebin ${lib.concatMapStringsSep " " (dep: dep.otpApplication) beamDeps}
 
       runHook postBuild
     '';