Please never do this.
Commas and full stops have meaning. You’re modifying the original quote without telling the reader that you have done so. How this became the accepted practice in so many style guides and grammar checkers I will never understand. I shall defer to Geoffrey Pullum’s Punctuation and human freedom , whose title is entirely appropriate, for justification. Steven Pinker’s The Sense of Style  can provide the unconvinced further justification.