Escape brackets in RSS item title

[trtbot]

If a rss title has a bracket, it breaks the markdown

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Context (Will only be viewable if you are a member of this guild)
Submitter (Discord Username): bcongdon (158708926299373568)
Channel: #morning-paper (426613124678942735)
Guild: The Round Table (426611271429783553)

[narendasan]

This applies to most markdown symbols, so it would need to be more comprehensive than just [

[bcongdon]

There must be some markdown escaper/sanitizer we can use...