docs: fix Decimal field prose to reference Field() instead of condecimal()

The 'Decimals in SQLModel' section introduced its example with 'using
the condecimal() function', but the example (and current SQLModel) uses
Field(max_digits=..., decimal_places=...). condecimal() is a Pydantic v1
constrained-type helper that SQLModel does not re-export, and using it as
an annotation trips static type checkers.

Reword the sentence to match the paragraph above it and the code sample,
both of which already use Field().

Signed-off-by: Anas Khan <83116240+anxkhn@users.noreply.github.com>

Author: anxkhn

docs/advanced/decimal.md

@@ -31,7 +31,7 @@ For the database, **SQLModel** will use [SQLAlchemy's `DECIMAL` type](https://do
 
 ## Decimals in SQLModel
 
-Let's say that each hero in the database will have an amount of money. We could make that field a `Decimal` type using the `condecimal()` function:
+Let's say that each hero in the database will have an amount of money. We could make that field a `Decimal` type and set the number of digits and decimal places in the `Field()` function:
 
 {* ./docs_src/advanced/decimal/tutorial001_py310.py ln[1:11] hl[11] *}