Update development Ruby version to 2.7.7

Author: jgarber623

.ruby-version

@@ -1 +1 @@
-2.7.6
+2.7.7

CONTRIBUTING.md

@@ -8,9 +8,9 @@ There are a couple ways you can help improve webmention-client-ruby:
 
 ## Getting Started
 
-webmention-client-ruby is developed using Ruby 2.7.6 and is additionally tested against Ruby 3.0 and 3.1 using [GitHub Actions](https://github.com/indieweb/webmention-client-ruby/actions).
+webmention-client-ruby is developed using Ruby 2.7.7 and is additionally tested against Ruby 3.0 and 3.1 using [GitHub Actions](https://github.com/indieweb/webmention-client-ruby/actions).
 
-Before making changes to webmention-client-ruby, you'll want to install Ruby 2.7.6. It's recommended that you use a Ruby version managment tool like [rbenv](https://github.com/rbenv/rbenv), [chruby](https://github.com/postmodern/chruby), or [rvm](https://github.com/rvm/rvm). Once you've installed Ruby 2.7.6 using your method of choice, install the project's gems by running:
+Before making changes to webmention-client-ruby, you'll want to install Ruby 2.7.7. It's recommended that you use a Ruby version managment tool like [rbenv](https://github.com/rbenv/rbenv), [chruby](https://github.com/postmodern/chruby), or [rvm](https://github.com/rvm/rvm). Once you've installed Ruby 2.7.7 using your method of choice, install the project's gems by running:
 
 ```sh
 bundle install

README.md

@@ -19,7 +19,7 @@
 
 Before installing and using webmention-client-ruby, you'll want to have [Ruby](https://www.ruby-lang.org) 2.7 (or newer) installed. It's recommended that you use a Ruby version managment tool like [rbenv](https://github.com/rbenv/rbenv), [chruby](https://github.com/postmodern/chruby), or [rvm](https://github.com/rvm/rvm).
 
-webmention-client-ruby is developed using Ruby 2.7.6 and is additionally tested against Ruby 3.0 and 3.1 using [GitHub Actions](https://github.com/indieweb/webmention-client-ruby/actions).
+webmention-client-ruby is developed using Ruby 2.7.7 and is additionally tested against Ruby 3.0 and 3.1 using [GitHub Actions](https://github.com/indieweb/webmention-client-ruby/actions).
 
 ## Installation