fix: separate html-proofer gem from Gemfile (#73)

* fix: separate html-proofer gem from Gemfile

* debug: remove .ruby-version (w/netlify changes)

Netlify config changes:
 - jekyll build -> bundle exec jekyll build
 - update node version to 20.x (from 10.x)

* Revert "debug: remove .ruby-version (w/netlify changes)"

This reverts commit 3f0d091.

* bundle, not gem

* debug: try ruby 3.3.3

* debug: bundle process

.github/workflows/main.yml

@@ -1,4 +1,7 @@
 name: htmlproofer
+
+# Validates all links are up to date on the website
+
 on:
   push:
     branches:
@@ -11,7 +14,7 @@ on:
 
 jobs:
   checklinks:
-    name: Linux
+    name: Check links
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
@@ -23,10 +26,11 @@ jobs:
         run: |
           gem update --system --no-document
           gem update bundler --no-document
-          gem install jekyll bundler
           bundle install
       - name: build jekyll
         run: bundle exec jekyll build
       - name: htmlproofer
         run: |
+          bundle add html-proofer
+          bundle install
           bundle exec htmlproofer ./_site

.ruby-version

@@ -1 +1 @@
-3.3.4
+3.3.3

Gemfile

@@ -1,3 +1,2 @@
 source "https://rubygems.org"
 gem 'github-pages', group: :jekyll_plugins
-gem 'html-proofer'