Update critical file(s) according to Chirpy v7.2.3

Gemfile

@@ -2,7 +2,7 @@
 
 source "https://rubygems.org"
 
-gem "jekyll-theme-chirpy", "~> 7.2"
+gem "jekyll-theme-chirpy", "~> 7.2", ">= 7.2.3"
 
 gem "html-proofer", "~> 5.0", group: :test
 

_config.yml

@@ -212,8 +212,9 @@ exclude:
   - tools
   - README.md
   - LICENSE
-  - "*.config.js"
+  - purgecss.js
-  - package*.json
+  - rollup.config.js
+  - "package*.json"
 
 jekyll-archives:
   enabled: [categories, tags]

_plugins/posts-lastmod-hook.rb

@@ -4,10 +4,10 @@
 
 Jekyll::Hooks.register :posts, :post_init do |post|
 
-  commit_num = `git rev-list --count HEAD "#{ post.path }"`.strip
+  commit_num = `git rev-list --count HEAD "#{ post.path }"`
 
   if commit_num.to_i > 1
-    lastmod_date = `git log -1 --pretty="%ad" --date=iso "#{ post.path }"`.strip
+    lastmod_date = `git log -1 --pretty="%ad" --date=iso "#{ post.path }"`
     post.data['last_modified_at'] = lastmod_date
   end