Auto merge of #19752 - CYBAI:fix-mako-true, r=nox

style: Use Python's True instead of string for arbitrary Python code in mako

As discussion in IRC with @nox and @gootorov , it's more correct to use Python's `True` for `${arbitrary Python code}` in mako.

Following is related IRC logs

```
15:39 nox
As I said, that's because there are 2 ways to invoke the things with Mako.

15:40 nox
${arbitrary Python code} vs <%named_helper ..>...</%named_helper>

15:40 nox
IIRC <%foo bar=True></%foo> is not valid Mako syntax,

15:40 nox
but with bar="True" it is.

15:42 cybai
gootorov: I did meet some issues when moving makos if I set "True" instead of Python's `True`. Thus, like nox mentioned above, it's related to how the code works

15:44 gootorov
nox: Alright, I got it now, thanks. There are a couple ${function} blocks that still use `boxed="True" though. They aren't <%named_helpers>, shouldn't they use Python's True too, then?

15:45 nox
gootorov: I think there is an issue because this specific attribute is also used as a string through other <%helpers>,

15:46 nox
gootorov: Seems like it's not an issue anymore because the boxed attribute is passed to arg_to_bool,

15:46 nox
which either returns the boolean as is or check whether it's a "True" or "False" string.

15:47 nox
gootorov: So indeed, you can probably make those use booleans now.

15:47 gootorov
nox: Okay, got it, thanks for the explanation :)
```

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests

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