Update context-functions.md: remove redundant indentation in code blocks

[unkarjedy]

There might be a more general issue with the .md files rendered used on the site.
It incorrectly handles indentation.
It removes indentation from the first line, but leaves remaining lines untouched.
IMO it shouldn't affect indentation at all, and all existing code blocks should be reviewed and the indentation should be removed.

Example of bad rendering:

[dwijnand]

@Florian3k can you see if we can address the root cause? We shouldn't remove the indentation on the first line.

[Florian3k]

Yes, that's definitely something to fix (created #18593 for this).

Another issue is that we have different indentation in code blocks throughout the documentation (sometimes none, sometimes whole snippet is indented by 2 spaces). Do we want to unify this, and if so which way?

[unkarjedy]

IMO it shouldn't affect indentation at all, and all existing code blocks should be reviewed and the indentation should be removed.
Florian3k can you see if we can address the root cause? We shouldn't remove the indentation on the first line.

And if it's fixed, ideally all pages should be reviewed for code examples with common indentation.
I noticed that one ^ by accident.
Some regexp-search for the first line could be used.