Fix deploy to GitHub Pages (#148)

Author: gomzyakov

Gemfile

@@ -1,5 +1,19 @@
 source "https://rubygems.org"
-gem 'github-pages', group: :jekyll_plugins
-gem 'jekyll-include-cache', group: :jekyll_plugins
-gem 'html-proofer'
-gem "webrick", "~> 1.7"
+ruby RUBY_VERSION
+
+# Hello! This is where you manage which Jekyll version is used to run.
+# When you want to use a different version, change it below, save the
+# file and run `bundle install`. Run Jekyll with `bundle exec`, like so:
+#
+#     bundle exec jekyll serve
+#
+
+# If you have any plugins, put them here!
+gem 'wdm', '>= 0.1.0' if Gem.win_platform?
+group :jekyll_plugins do
+    gem 'github-pages'
+    gem 'jekyll-include-cache'
+    gem 'jekyll-titles-from-headings'
+    gem 'jekyll-feed'
+    gem 'jekyll-sitemap'
+end

Gemfile.lock

@@ -100,15 +100,6 @@ GEM
     html-pipeline (2.14.3)
       activesupport (>= 2)
       nokogiri (>= 1.4)
-    html-proofer (4.4.3)
-      addressable (~> 2.3)
-      mercenary (~> 0.3)
-      nokogiri (~> 1.13)
-      parallel (~> 1.10)
-      rainbow (~> 3.0)
-      typhoeus (~> 1.3)
-      yell (~> 2.0)
-      zeitwerk (~> 2.5)
     http_parser.rb (0.8.0)
     i18n (1.14.7)
       concurrent-ruby (~> 1.0)
@@ -241,12 +232,10 @@ GEM
     octokit (4.25.1)
       faraday (>= 1, < 3)
       sawyer (~> 0.9)
-    parallel (1.26.3)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
     public_suffix (5.1.1)
     racc (1.8.1)
-    rainbow (3.1.1)
     rb-fsevent (0.11.2)
     rb-inotify (0.11.1)
       ffi (~> 1.0)
@@ -272,18 +261,19 @@ GEM
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
     unicode-display_width (1.8.0)
-    webrick (1.9.1)
-    yell (2.2.2)
-    zeitwerk (2.6.18)
 
 PLATFORMS
   x86_64-linux-musl
 
 DEPENDENCIES
   github-pages
-  html-proofer
+  jekyll-feed
   jekyll-include-cache
-  webrick (~> 1.7)
+  jekyll-sitemap
+  jekyll-titles-from-headings
+
+RUBY VERSION
+   ruby 2.7.1p83
 
 BUNDLED WITH
    2.2.24

_config.yml

@@ -10,12 +10,10 @@ include:
   - LICENSE
 
 plugins:
-  - jekyll-remote-theme
   - jekyll-include-cache
-  - jekyll-avatar
-  - jemoji
-  - jekyll-mentions
   - jekyll-titles-from-headings
+  - jekyll-feed
+  - jekyll-sitemap
 
 # Exclude the `vendor` folder created by build process
 exclude: