Extend `CommonChecks.DebugFunctions` to look for calls to `dbg`

[angelikatyborska]

• Extend the module ElixirAnalyzer.ExerciseTest.CommonChecks.DebugFunctions to also find calls to dbg()
• Add tests
• Update comment https://github.com/exercism/website-copy/blob/main/analyzer-comments/elixir/solution/debug_functions.md

[elfenlaid]

Replying to https://mas.to/@angelikatyborska/110878322509896396

I'd like to give it a try, if you don't mind 🙏

[angelikatyborska]

@elfenlaid Awesome! Ping me here if you have any questions.

[angelikatyborska]

Done and deployed 🙌

[elfenlaid]

Awesome, thanks 🙇