Update docs/contributing/writing-docs-guide.md

Co-authored-by: Steve Piercy <[email protected]>

Author: ksuess

docs/contributing/writing-docs-guide.md

@@ -263,7 +263,7 @@ This would be rendered as:
 ````{admonition} f-strings can make your life easier
 :class: toggle
 
-To use formatted string literals, begin a string with f or F before the opening quotation mark or triple quotation mark.
+To use formatted string literals, begin a string with `f` or `F` before the opening quotation mark or triple quotation mark.
 Inside this string, you can write a Python expression between { and } characters that can refer to variables or literal values.
 
 ```{code-block} python