Update maturity-model.md - minor formatting change

Moved a split sentence into a single line, trying to solve a rendering issue on GitBook.
"development" and "forge" are rendered without a space between the two words.

Author: dellagustin-sap

patterns/2-structured/maturity-model.md

@@ -33,8 +33,7 @@ InnerSource project differs depending on each team.
 Teams sharing InnerSource learnings run into misunderstandings as they are not
 aware of their respective level of InnerSource adoption.
 
-Teams believe that "it's all about migrating to a shared software development
-[forge](https://en.wikipedia.org/wiki/Forge_%28software%29)" (GitLab, GitHub, or Bitbucket being well known examples of such forges).
+Teams believe that "it's all about migrating to a shared software development [forge](https://en.wikipedia.org/wiki/Forge_%28software%29)" (GitLab, GitHub, or Bitbucket being well known examples of such forges).
 
 Teams are not aware of best practices that would help them solve issues that
 they run into in their daily doing.