closes #2523 add more examples for derive_var_joined_exist_flag

[rossfarrugia]

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[rossfarrugia]

This one doesn't warrant a NEWS entry in my mind.

[github-actions]

Package	Line Rate	Health
admiral	97%	✔
Summary	97% (4978 / 5140)	✔

[bms63]

I think it is nice to mention in the news!! It is also reminds us to write it up in the blog

[bms63]

@yurovska just checking if these new examples from @rossfarrugia (TYTY) would of assuaged some of your frustrations with admiral!?

[yurovska]

@yurovska just checking if these new examples from @rossfarrugia (TYTY) would of assuaged some of your frustrations with admiral!?

I wouldn’t say I was ever frustrated. {admiral} is awesome! It was more about me facing some challenges due to my lack of experience. These examples definitely help, though - thanks!

[bms63]

The prodigal son returns