feat(wpcarro/emacs): Install tvl Elisp

All I know is that this extends my magit configuration for Gerrit support.

Change-Id: I35c9a264ff25ce6e08b7033e0e022d4047021f05
Reviewed-on: https://cl.tvl.fyi/c/depot/+/4357
Tested-by: BuildkiteCI
Reviewed-by: wpcarro <wpcarro@gmail.com>

users/wpcarro/emacs/default.nix

@@ -33,6 +33,10 @@ let
   emacsWithPackages = (emacsPackagesGen emacs27).emacsWithPackages;
 
   wpcarrosEmacs = emacsWithPackages (epkgs:
+    (with epkgs.tvlPackages; [
+      tvl
+    ]) ++
+
     (with epkgs.elpaPackages; [
       exwm
     ]) ++