.github: continue finessing the text and names for nixpkgs-vet (#339354)

.github/workflows/nixpkgs-vet.yml

@@ -1,6 +1,8 @@
-# Checks pkgs/by-name (see pkgs/by-name/README.md) using the `nixpkgs-vet` tool (see https://github.com/NixOS/nixpkgs-vet)
+# `nixpkgs-vet` is a tool to vet Nixpkgs: its architecture, package structure, and more.
+# Among other checks, it makes sure that `pkgs/by-name` (see `../../pkgs/by-name/README.md`) follows the validity rules outlined in [RFC 140](https://github.com/NixOS/rfcs/pull/140).
 # When you make changes to this workflow, please also update `ci/nixpkgs-vet.sh` to reflect the impact of your work to the CI.
-name: Check pkgs/by-name
+# See https://github.com/NixOS/nixpkgs-vet for details on the tool and its checks.
+name: Vet nixpkgs
 
 on:
   # Using pull_request_target instead of pull_request avoids having to approve first time contributors.
@@ -18,7 +20,7 @@ permissions: {}
 
 jobs:
   check:
-    name: pkgs-by-name-check
+    name: nixpkgs-vet
     # This needs to be x86_64-linux, because we depend on the tooling being pre-built in the GitHub releases.
     runs-on: ubuntu-latest
     # This should take 1 minute at most, but let's be generous. The default of 6 hours is definitely too long.