[Python] Add SQL syntax highlighting in f-strings

[deathaxe]

Resolves #3885

This PR proposes to add support for SQL syntax highlghting within f-strings.

I have no strong opinion about adding this. The change was easy, so proposing it for thosw who want it.

Note: With #3046 Python's syntax cache grows from about 3MB to 4MB with this PR merged.

[jrappen]

Appreciate the notes in the commit message.

[FichteFoll]

I'd like to see an actual use case of using SQL with an f-string before adding this, considering that it significantly increases the cache size along with #3046 (by 33%!) for what seems like rather little gain. I have some ideas for building an sql statement from a string where a prepared statement (with proper value insertion) would not suffice, but I still doubt whether an f-string is the best or even a proper solution in those cases.