Exception message doesn't follow doc style guide

[coke]

The Problem

my class X::Syntax::Comment::Embedded does X::Syntax {
    method message() { "Opening bracket required for #` comment" }
}

the perl6/doc styleguide requires that we use "curly brace" here instead of bracket, and we have a currently failing test:

$ xt/braces.t doc/Type/X/Syntax/Comment/Embedded.pod6
1..1
not ok 1 - doc/Type/X/Syntax/Comment/Embedded.pod6: Found 'bracket' without 'square' or 'angle'.
# Failed test 'doc/Type/X/Syntax/Comment/Embedded.pod6: Found 'bracket' without 'square' or 'angle'.'
# at xt/braces.t line 37
# Looks like you failed 1 test of 1

While not a must have, I think following the doc style guide for this exception is correct (and then we can update the text in the doc site and then pass the test)

[AlexDaniel]

OK, first of all, I'm unable to trigger that message.

Secondly, the proposed change is incorrect here. In the doc repo, curly brace is used to refer to {. However, this error message talks about any opening bracket that is supported by #` (through unicode). It can be changed to something more generic (like opener or something better).

[AlexDaniel]

That error message looks like bitrot to me. Last related changes to the code are 7 years ago or so:

• Exception d63e72d
• Grammar f0291ac

I can't even use bisectable for that because it can only go back to 2014.01.