discussions: GitHub emojis render as undefined

[lowlighter]

Discussed in #740

^{Originally posted by cherryblossom000 January 5, 2022}
Example

The emoji of the General Feedback category is :octocat:. This is rendered as undefined, even if config_gemoji: true.

Possible fix:

metrics/source/plugins/discussions/index.mjs

Line 36 in 63a84e2

for (const category of [...fetched.map(({category:{emoji, name}}) => `${imports.emoji.get(emoji)} ${name}`)])

- for (const category of [...fetched.map(({category:{emoji, name}}) => `${imports.emoji.get(emoji)} ${name}`)]) 
+ for (const category of fetched.map(({category:{emoji, name}}) => `${imports.emoji.get(emoji) ?? emoji} ${name}`))
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