vuejs / vue Public

* feat(compiler): template staticClass no longer preserves whitespace

Template static classes used to preserve whitespace after compilation, resulting in builds that had
bigger file outputs with whitespace in component's staticClass attributes

fix #12113

* refactor(refactor(web-compiler): removed ignore in regex): Removed ignore flag in regex

fix #12113

* test(ssr-string.spec.js): Removed newline character, as whitespace is purged in static classes

There's no need to escape newlines in static classes, as they're now replaced with a single
whitespace character

fix #12113

* test(directives/class.spec.js): Added whitespace to test

fix #12113

* Apply suggestions from code review

Co-authored-by: Eduardo San Martin Morote <[email protected]>