Property.findSeparator is scanning strings character-by-character

[InPermutation]

Related to #16 #17 #18 - findSeparator is also showing up in my profiler as a significant CPU user; I think it can be significantly sped up by using e.g.

for (const match of this.linesContent[0].matchAll(/[\t\f :=]/g)) {
  if (!match.index) { continue; }

  const position = match?.index

but I haven't finished drafting the PR, so I'm filing this Issue instead 😎

[nbouvrette]

@InPermutation the fix is now available in 3.3.2

Let me know if you see anything I might have missed.