vgrep: make test more robust (#91180)
vgrep: make test more robust (#91180)

The test currently fails on ARM, no need to check for all these weird characters:

Minitest::Assertion: Expected /Hello\ from\ \x1B\[01;31m\x1B\[KHomebrew\x1B\[m\x1B\[K!\n/ to match "\e[95m\e[4mIndex\e[0m\e[0m \e[94m\e[4mFile      \e[0m\e[0m \e[92m\e[4mLine\e[0m\e[0m \e[4mContent\e[0m\n\e[95m    0\e[0m \e[94m./test.txt\e[0m \e[92m   1\e[0m Hello from \e[0m\e[1m\e[31mHomebrew\e[0m!\n".
makigumo/homebrew-core,cblecker/homebrew-core,lemzwerg/homebrew-core,chrisfinazzo/homebrew-core,sjackman/homebrew-core,filcab/homebrew-core,stgraber/homebrew-core,Homebrew/homebrew-core,cblecker/homebrew-core,stgraber/homebrew-core,mfikes/homebrew-core,zyedidia/homebrew-core,zyedidia/homebrew-core,sjackman/homebrew-core,filcab/homebrew-core,adam-moss/homebrew-core,nbari/homebrew-core,uyjulian/homebrew-core,chrisfinazzo/homebrew-core,mfikes/homebrew-core,nbari/homebrew-core,uyjulian/homebrew-core,adam-moss/homebrew-core,nandub/homebrew-core,nandub/homebrew-core,makigumo/homebrew-core,lemzwerg/homebrew-core,Homebrew/homebrew-core