[defns.component] Remove unwarranted italics

Fixes ISO/CS 018 (C++23 DIS).

Author: jensmaurer

source/intro.tex

@@ -224,13 +224,9 @@
 return types
 
 \begin{defnote}
-For example, the class template
-\tcode{basic_string}
-and the non-member
-function templates
-that operate on
-strings are referred to as the
-\term{string component}.
+For example, the class template \tcode{basic_string}
+and the non-member function templates
+that operate on strings are referred to as the string component.
 \end{defnote}
 
 \indexdefn{behavior!conditionally-supported}%