Allow users to comment .take-issue without taking

[damccorm]

Right now, there's no way for committers (or other users) to tell non-committers about the .take-issue command without taking the issue. This updates the command to ignore usages that are bracketed by ` markdown characters.

Part of #21684

✨ Rendered doc changes ✨

Example of this working - damccorm/playground#8

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[asf-ci]

Can one of the admins verify this patch?

[asf-ci]

Can one of the admins verify this patch?

[asf-ci]

Can one of the admins verify this patch?

[damccorm]

R: @lostluck @aaltay

[lostluck]

Love me a good backtic.