Drop support for `jekyll-watch-1.4.0` and older (#7287)
Drop support for `jekyll-watch-1.4.0` and older (#7287)

Merge pull request 7287
jaybe-jekyll/jekyll,tillgrallert/jekyll,jaybe-jekyll/jekyll,jaybe-jekyll/jekyll,chrisfinazzo/jekyll,jaybe-jekyll/jekyll,jekyll/jekyll,fulldecent/jekyll,jekyll/jekyll,Strangehill/jekyll,tillgrallert/jekyll,ryanshaw/jekyll,ryanshaw/jekyll,ryanshaw/jekyll,fulldecent/jekyll,x-way/jekyll,yhironaka/yhironaka.github.io,ryanshaw/jekyll,chrisfinazzo/jekyll,x-way/jekyll,tillgrallert/jekyll,x-way/jekyll,Strangehill/jekyll,Strangehill/jekyll,fulldecent/jekyll,jekyll/jekyll,jekyll/jekyll,Strangehill/jekyll,fulldecent/jekyll,tillgrallert/jekyll,chrisfinazzo/jekyll,chrisfinazzo/jekyll,Strangehill/jekyll,x-way/jekyll,tillgrallert/jekyll