Fix README.md typos

Signed-off-by: Colin Bartlett <[email protected]>

README.md

@@ -1,6 +1,6 @@
 # Phlex::PDF
 
-Phlex PDF lets you compose PDF files with components in pure Ruby. It's a thin layer sits on the shoulder of giants, [Prawn](https://github.com/prawnpdf/prawn), that encourages a component-first approach to building PDF documents.
+Phlex PDF lets you compose PDF files with components in pure Ruby. It's a thin layer that sits on the shoulder of giants, [Prawn](https://github.com/prawnpdf/prawn), that encourages a component-first approach to building PDF documents.
 
 ## Installation
 
@@ -55,12 +55,12 @@ To install this gem onto your local machine, run `bundle exec rake install`. To
 
 ## Contributing
 
-Bug reports and pull requests are welcome on GitHub at https://github.com/phlex-ruby/phlex-pdf. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [code of conduct](https://github.com/[USERNAME]/phlex-pdf/blob/main/CODE_OF_CONDUCT.md).
+Bug reports and pull requests are welcome on GitHub at https://github.com/phlex-ruby/phlex-pdf. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [code of conduct](https://github.com/phlex-ruby/phlex-pdf/blob/main/CODE_OF_CONDUCT.md).
 
 ## License
 
 The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).
 
 ## Code of Conduct
 
-Everyone interacting in the Phlex::Pdf project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct](https://github.com/[USERNAME]/phlex-pdf/blob/main/CODE_OF_CONDUCT.md).
+Everyone interacting in the Phlex::PDF project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct](https://github.com/phlex-ruby/phlex-pdf/blob/main/CODE_OF_CONDUCT.md).