Incorrect highlighting if deprecation message contains `]` character

Prerequisites

Please put an X between the brackets as you perform the following steps:

[x] Check that your issue is not already filed: https://github.com/leanprover/lean4/issues
[x] Reduce the issue to a minimal, self-contained, reproducible test case. Avoid dependencies to Mathlib or Batteries.
[x] Test your test case against the latest nightly release, for example on https://live.lean-lang.org/#project=lean-nightly (You can also use the settings there to switch to “Lean nightly”)

Description

The following code produces incorrect highlighting in VS Code in recent (post-#3968) Lean releases:

@[deprecated Array.get? "Use a[i]? or a.get? i instead"]
def Array.atIndex? (a : Array α) (i : Nat) : Option α :=
  a.get? i

The web editor at live.lean-lang.org seems to be unaffected by this issue.

An interesting variant of this is

@[deprecated Array.get? "Use `a[i]?` or `a.get? i` instead", inherit_doc Array.get?]

where the highlighting is only broken until the end of the attribute.

Steps to Reproduce

Create a new Lean project on a recent nightly and paste in the above code

Expected behavior: Highlighting should work as usual

Actual behavior: Highlighting gets confused by the ] character in the deprecation message.

Versions

4.11.0-nightly-2024-08-05
Linux markus-z16 6.9.12-200.fc40.x86_64 leanprover/lean4#1 SMP PREEMPT_DYNAMIC Sat Jul 27 15:56:15 UTC 2024 x86_64 GNU/Linux
vscode-lean4 v.0.0.176 in VS Code 1.92.0

Impact

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leanprover / vscode-lean4