[feature request] `indentRainbow.markLinePatterns` to highlight lines which are wrongly indented

[joshinils]

I've found that setting up a regex for ignoring some lines also made it necessary to include others.

"indentRainbow.ignoreLinePatterns" : [
    "/^(    )*  \\| [^\\s\\n]/gm",
]

This ignores lines where a pipe is at a specific location when indenting with 4 spaces:

This correctly ignores lines 27 and 31.

However, I'd like to have this as a counterpart:

"indentRainbow.markLinePatterns" : [
    "/^(    )*\\|/gm",
]

Such that lines 5, 13, 21, 29, and 37 are also marked in red as incorrect, they start with a multiple of four spaces where the next character is a pipe.