nix: use tag for rev in ctags derivation

Author: keegancsmith

flake.nix

@@ -18,12 +18,12 @@
       in { default = import ./shell.nix { inherit pkgs; }; });
     # Pin a specific version of universal-ctags to the same version as in cmd/symbols/ctags-install-alpine.sh.
     overlays.ctags = self: super: rec {
-      my-universal-ctags = super.universal-ctags.overrideAttrs (old: {
+      my-universal-ctags = super.universal-ctags.overrideAttrs (old: rec {
         version = "6.0.0";
         src = super.fetchFromGitHub {
           owner = "universal-ctags";
           repo = "ctags";
-          rev = "3af413544a0ed0a4c52200894cfd6391f06d2e94";
+          rev = "v${version}";
           sha256 = "sha256-XlqBndo8g011SDGp3zM7S+AQ0aCp6rpQlqJF6e5Dd6w=";
         };
         # disable checks, else we get `make[1]: *** No rule to make target 'optlib/cmake.c'.  Stop.`