Trim whitespace

Author: aholten

docs/tutorial/relationship-attributes/type-annotation-strings.md

@@ -16,7 +16,7 @@ In the first Relationship attribute, we declare it with `List["Hero"]`, putting
 
 ///
 
-What's that about? Can't we just write it normally as `List[Hero]`? 
+What's that about? Can't we just write it normally as `List[Hero]`?
 
 By that point, in that line in the code, the Python interpreter **doesn't know of any class `Hero`**, and if we put it just there, it would try to find it unsuccessfully, and then fail. 😭 
 
@@ -26,7 +26,7 @@ But by putting it in quotes, in a string, the interpreter sees it as just a stri
 
 But the editor and other tools can see that **the string is actually a type annotation inside**, and provide all the autocompletion, type checks, etc. 🎉
 
-And of course, **SQLModel** can also understand it in the string correctly. ✨ 
+And of course, **SQLModel** can also understand it in the string correctly. ✨
 
 That is actually part of Python, it's the current official solution to handle it.